TEST BANK for Dental Materials: Foundations and Applications 11th Edition. by Powers John & Wataha J by StudyGuide

Dental Materials 11th Edition Powers Test Bank Chapter 01: Introduction to Restorative Dental Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. What causes caries? a. Food debris b. Materia alba c. Acidic foodstuff d. Bacterial plaque e. Salivary glycoproteins ANS: D

A B

D E

Feedback Food debris does not have the structural organization of bacterial plaque biofilm. Materia alba does not have the structural organization of bacterial plaque biofilm. Acidic foodstuff lowers pH and may demineralize teeth but does not directly cause decay. Caries is caused by biofilm; also known as bacterial plaque. Salivary glycoproteins form the acquired enamel pellicle to which bacteria adhere.

DIF: Knowledge REF: p. 1 OBJ: 2 TOP: CDA, GC, V, A,1b. Patient Education and Oral Health Management MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 2. Caries is most likely to occur on which of the following tooth surfaces? a. Buccal b. Lingual c. Occlusal d. Interproximal e. C and D are both correct. ANS: E

C D

Feedback Buccal surfaces are also susceptible to caries; however, there is less surface area left unchecked. Lingual surfaces are also susceptible to caries; however, there is less surface area left unchecked. Caries is most likely to occur in pits and fissures on the occlusal surface and on interproximal tooth surfaces where plaque accumulates unchecked. Caries is most likely to occur in pits and fissures on the occlusal surface and on interproximal tooth surfaces where plaque accumulates unchecked.

Caries is most likely to occur in pits and fissures on the occlusal surface and on interproximal tooth surfaces where plaque accumulates unchecked.

DIF: Knowledge REF: p. 1 OBJ: 2 TOP: CDA, GC, III, B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam, c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. Which of the following is an intracoronal restoration? a. Ceramic–alloy crown on tooth number 21 b. Ceramic veneer on tooth number 8 c. Ceramic onlay on tooth number 30 d. Ceramic inlay on tooth number 14 ANS: D

A B C

Feedback The alternate choices are all extracoronal restorations used to repair the external. The alternate choices are all extracoronal restorations used to repair the external. The alternate choices are all extracoronal restorations used to repair the external. A ceramic inlay on tooth number 14 is an example of an intracoronal restoration, meaning that the restoration is being used to repair damage restricted to the internal parts of a tooth. Materials such as amalgam and composite resin are used in addition to ceramic or cast metal.

DIF: Knowledge REF: p. 4 OBJ: 3 TOP: CDA, GC, III, B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam, c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. What is the process called where decay is removed from the tooth in order for a restoration to

be placed? a. Cavity preparation b. Convenience form c. Margination d. Extension ANS: A

B C D

Feedback The process is referred to as cavity preparation. Cavity preparation is used to remove diseased or damaged tissue and provide a space accessible for restoration and one that can stably retain the restoration. Convenience form is a term describing the nature of the cavity preparation. Extension is a term describing the nature of the cavity preparation. Margination is the procedure for finishing the margins of a restoration.

DIF: Knowledge

REF: p. 4

OBJ: 2

TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. Which of the following is an example of an intracoronal (direct) restoration? a. Laboratory-cured composite b. Dental amalgam c. Ceramic veneer d. Cast crown ANS: B

C D

Feedback Laboratory-cured composite is a restoration that is constructed away from the patient in the dental laboratory. Dental amalgam is an example of a direct restoration. All of the other restorations are prepared away from the tooth and then cemented or bonded to the tooth using a procedure that is independent of the manufacturer of the restoration. Ceramic veneer is a restoration that is constructed away from the patient in the dental laboratory. Cast crown is a restoration that is constructed away from the patient in the dental laboratory.

DIF: Knowledge REF: p. 4 OBJ: 3 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 ProvidinTgESS upTpB orA tivNeKTS reE atL mL enEt R Se.rvCicOeM s, 6.5 General 6. Which of the following is an example of an extracoronal restoration? Choose all that apply. a. Ceramic inlay b. Ceramic–alloy crown c. Porcelain jacket crown d. A, B, and C e. A and C ANS: D

Feedback All three restorations involve lab procedures and are examples of indirect restorations. All three restorations involve lab procedures and are examples of indirect restorations. All three restorations involve lab procedures and are examples of indirect restorations. All three restorations involve lab procedures and are examples of indirect restorations. All three restorations involve lab procedures and are examples of indirect restorations.

DIF: Knowledge REF: p. 5 OBJ: 3 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. Which of the following is an example of an extracoronal restoration? a. Disto-occlusal ceramic inlay on tooth number 29 b. Buccal Cl. V composite resin on tooth number 31 c. Mesio-occlusal gold onlay on tooth number 15 d. Mesio-occlusal amalgam on tooth number 13 ANS: C

B C

Feedback This is an example of intracoronal restoration because it fits within the internal borders of the anatomical crown. This is an example of intracoronal restoration because it fits within the internal borders of the anatomical crown. An onlay involves an inlay with extension to cover or protect a cusp. Thus a mesio-occlusal gold onlay on tooth number 15 is an example of an extracoronal restoration. This is an example of intracoronal restoration because it fits within the internal borders of the anatomical crown.

DIF: Knowledge REF: p. 5 OBJ: 3 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

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8. Which material is used to fill the root canal once all of the pulpal tissue has been removed? a. Silver point b. Paper points c. Dental cement d. Moisture-resistant sealer ANS: D

A B C

Feedback Silver master points are no longer used to fill canals. Paper points are used to dry the canal after irrigation. Dental cements may be used to seal the access opening but are not suited to fill the canals. The space created when the pulpal tissues are removed must be replaced with sealers that prevent ingress of bacteria that comes with moisture.

DIF: Knowledge REF: p. 5 OBJ: 4 TOP: CDA, GC, II. B.2. h. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to h. endodontic therapy MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. A(n)

is also known as a bridge.

a. b. c. d.

removable partial denture fixed partial denture abutment pontic

ANS: B

Feedback A removable partial denture may be removed by the patient and is not known as a bridge. A fixed (cemented) partial denture is commonly known as a bridge. The crown preparation portions of the bridge are called abutments, and the missing tooth replacement is called the pontic. An abutment is an individual component of a fixed partial denture and is not known as a bridge. A pontic is an individual component of a fixed partial denture and is not known as a bridge.

DIF: Knowledge REF: p. 9 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. A resin-bonded fixed partial denture is sometimes used under which conditions? a. Bridge has only one abutment. b. Abutment teeth have bT eeEnSeT ndBoA doNnKtiS caEllL yL trE eaRte.dC . OM c. Abutment teeth are healthy and free of major restorations. d. The bridge has a long span involving more than four teeth. ANS: C

B C

Feedback Placement of crowns on the abutment teeth requires substantial sacrifice of tooth structure regardless of the condition of the abutment tooth. Endodontically treated teeth become brittle over time once the blood supply has been removed. The teeth need additional reinforcement. A resin-bonded fixed partial denture may be used when the abutment teeth are healthy and free of major restorations. Case selection is critical, because retention problems may occur with this type of restoration. Long span bridges require a significant amount of retention. A resin-bonded fixed partial, bridge.

DIF: Knowledge REF: p. 10 OBJ: 5 TOP: CDA, GC, II. B.2. h. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge preparation/cementation MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. The

of a fixed partial denture fills the edentulous space.

a. b. c. d.

pontic obturator abutment connector

ANS: A

B C D

Feedback The artificial replacement tooth used to fill the edentulous space of a fixed bridge is called a pontic. An obturator is used to fill tissue defects due to an accident or disease. The crowned teeth are called abutments. A connector joins crowns to pontics.

DIF: Comprehension REF: p. 9 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge preparation/cementation MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. Dental implants are commonly fabricated from _ a. dental amalgam b. titanium c. gold d. iron

-based metal alloys.

ANS: B

A B

C D

Feedback Dental amalgam is used to fill intracoronal restorations. Dental implants are commonly fabricated from titanium alloys. The surface of the implant may be titanium oxide or may be treated with other materials. Gold is used to fabricate extracoronal restorations. Iron is not a metal used in the oral environment.

DIF: Knowledge REF: p. 11 OBJ: 5 TOP: CDA, GC, II. B.2. m. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to m. implants MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. Which of the following types of implants are placed into but not through bone? a. Subperiosteal b. Transosseous c. Endosseous d. Mucosal ANS: C

Feedback A subperiosteal implant is placed between the bone and the overlying soft

B C

tissue. A transosseous (staple) implant is placed through bone (e.g., the mandible). An endosseous implant is placed into but not through bone. It is usually a single tooth form. A mucosal implant is placed between the bone and overlying soft tissue.

DIF: Knowledge REF: p. 11 OBJ: 5 TOP: CDA, GC, II. B.2. m. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to m. implants MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 14. Which of the following is an advantage of endosseous implant placement when contrasted

with fixed bridgework? Endosseous implants a. leave adjacent teeth unrestored. b. do not require invasive surgery. c. are less costly than fixed partial dentures. d. require floss threaders to clean abutment teeth. ANS: A

A B C D

Feedback Endosseous implants leave adjacent teeth unrestored. Endosseous implants require a surgical procedure. Endosseous implants are relatively costly. Fixed partial dentures require floss threaders to clean abutment teeth.

DIF: Knowledge REF: p. 11 OBJ: 5 TOP: CDA, GC, II. B.2. m. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to m. implants MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. Which type of crown is placed on an implant? a. Direct intracoronal b. Direct extracoronal c. Indirect intracoronal d. Indirect extracoronal ANS: D

A B C D

Feedback A direct intracoronal restoration is fabricated in the mouth. Direct extracoronal restorations for implants do not exist. An indirect intracoronal restoration is surrounded by tooth structure. An indirect extracoronal crown is placed on an implant.

DIF: Knowledge REF: p. 10 OBJ: 5 TOP: CDA, GC, II. B.2. m. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to m. implants MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

16. When would removable partial dentures be indicated? a. Replacement of single missing teeth b. Replacement of multiple missing teeth in multiple locations c. Situations where there is a distal abutment tooth to anchor a fixed bridge d. A and C e. B and C ANS: B

D E

Feedback Fixed partial dentures or single tooth implants are appropriate for replacement of single missing teeth. Removable partial dentures are appropriate for replacement of multiple missing teeth in multiple locations. Removable partial dentures are appropriate for situations in which there is not a distal abutment tooth to anchor a fixed partial denture. A and C are incorrect answers. C is an incorrect answer, but B is a correct answer.

DIF: Comprehension REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. The abutment teeth of a removable partial denture are engaged by what method? a. Ceramic–alloy crowns b. All-ceramic crowns c. Pontics d. Clasps ANS: D

A B C D

Feedback Abutment teeth of a removable partial denture may be restored with crowns. Abutment teeth of a removable partial denture may be restored with crowns. Pontics are artificial teeth used with fixed partial dentures to restore edentulous spaces. Abutment teeth of a removable partial denture are engaged by clasps.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. V. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to V. removable partials or full dentures MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. Which of the following statements is true of removable partial dentures? a. Removable partial dentures use a framework made of acrylic. b. The partial denture framework rests on tissue.

c. The partial denture framework rests on specific abutment teeth. d. The partial denture framework rests on specific pontic teeth. ANS: C

A B C D

Feedback The framework is made of metal. The acrylic portion of a removable partial denture rests on tissue. The framework of a removable partial denture rests on specific abutment teeth. Pontic teeth are associated with fixed rather than removable partial dentures.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. v. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to v. removable partials and full dentures MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. What types of teeth are bonded to the framework of removable partial dentures? a. Resin composite b. Ceramic c. Acrylic d. Alloy ANS: B

A B C D

Feedback Ceramic teeth are noTt E usSeT dB foAr N reK mSoE vaLbL leEpR ar.tiC alOdM entures. Acrylic teeth are bonded to the framework of removable partial dentures. Resin composite is used as an esthetic restorative material. Teeth cast in alloy are not used for removable partial dentures.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. v. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to v. removable partials or full dentures MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Which of the following is an advantage of removable partial dentures over fixed partial

dentures? a. Removable partial dentures are more esthetic. b. Removable partial dentures are more comfortable. c. With removable partial dentures, it is easier to clean and inspect the remaining teeth. d. Teeth adjacent to the edentulous space can be used to anchor dentures. ANS: C

Feedback Fixed partial dentures (fixed bridgework) are more esthetic and more comfortable.

Fixed partial dentures (fixed bridgework) are more esthetic and more comfortable. It is easier to clean and inspect the remaining teeth with removable partial dentures. This is a technique used with fixed partial dentures, not removable partial dentures.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to v. removable partial or full dentures MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Which type of restoration is recommended for an edentulous patient? a. Complete denture b. Fixed partial denture c. Removable partial denture d. Acid-etched resin-bonded bridge ANS: A

C D

Feedback A complete denture is appropriate for an edentulous patient. The complete denture may be fixed to tissue or to dental implants for retention. A three-unit fixed partial denture is a fixed restoration that is anchored to stable teeth in the same arcThE . STBANKSELLER.COM A removable partial denture is a fixed restoration that is anchored to stable teeth in the same arch. An acid-etched resin-bonded bridge is a fixed restoration that is anchored to stable teeth in the same arch.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. v. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to v. removable partials or full dentures MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. The phrase fixed bridge is a common term to describe which type of restoration? a. Complete denture b. Fixed partial denture c. Single tooth implant d. Removable partial denture ANS: B

A B C

Feedback A complete denture is a removable denture. Fixed bridge is analogous to fixed partial denture. A single tooth implant is not an example of a multiunit restoration.

A removable partial denture is a removable denture.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Fluoride gels, rinses, and varnishes are highly effective at treating which dental condition? a. Caries b. Drifting c. Staining d. Gingival recession ANS: A

A B C D

Feedback Fluoride gels, rinses, and varnishes are highly effective at preventing caries. Treating periodontitis and restoring edentulous spaces prevent drifting of teeth. Some forms of fluoride will stain teeth. Using the correct toothbrushing technique and avoiding periodontitis prevent gingival recession.

DIF: Knowledge REF: p. 12 OBJ: 6 TOP: CDA, GC, II. B.2. j. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to j. fluoride application MSC: NBDHE, 5.0 Using Preventive Agents, 5.1.2 Toxicology 24. Acid etching is used to bond pit and fissure sealant material to which tooth tissue? a. Enamel b. Dentin c. Cementum d. Dental pulp ANS: A

B C

Feedback Pit and fissure sealants are bonded to enamel that is typically etched with phosphoric acid before bonding. Dentin must be restored with a heavier weight material such as composite resin. Cementum must be restored with a heavier weight material such as composite resin. Dental pulp exposure must be treated endodontically.

DIF: Knowledge REF: p. 12 OBJ: 6 TOP: CDA, GC, III.D.2. e. Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using Preventive Agents, 5.2.2 Techniques for application 25. What is the purpose of mouth protectors?

a. b. c. d.

Trauma Temporomandibular arthritis Orthodontic crowding of teeth Insufficient vertical dimension

ANS: A

A B C D

Feedback Mouth protectors are used to prevent trauma to the oral structures during sports. Temporomandibular arthritis is a disease process. Orthodontic treatment is performed to relieve crowding. Insufficient vertical dimension is corrected using a partial or complete denture.

DIF: Knowledge REF: p. 12 OBJ: 6 TOP: CDA, GC. IV. B. 3. Laboratory materials and procedures MSC: NBDHE, 5.0 Using Preventive Agents, 5.3 Other preventive agents 26. Which tooth surface is most susceptible to caries in older adults? a. Pits and fissures of the occlusal surface b. Cervical smooth surface of all teeth c. Exposed root surfaces of all teeth d. Interproximal areas of all teeth ANS: C

C D

Feedback Pits and fissures of tT heEoScT clB usAaN l sKuS rfE acLeLaE reRty.pCicOaM lly more vulnerable at the time of eruption. Cervical smooth surfaces of all teeth are susceptible at any age based on oral hygiene habits. While all tooth surfaces can be susceptible to caries, exposed cementum is more vulnerable than enamel for caries formation due to its softer composition. Interproximal areas of all teeth are susceptible at any age based on oral hygiene habits.

DIF: Knowledge REF: p. 1 OBJ: 2 TOP: CDA, GC, V. A.1b. Patient Education and Oral Health Management MSC: NBDHE, 3.0 Planning and Managing Dental Hygiene Care, 3.3.2.1 Dental Caries 27. Which areas of the teeth are most susceptible to caries? a. Interproximal b. Occlusal c. Lingual d. All of the above are correct. e. Only A and B are correct. ANS: E

Feedback

C D E

Interproximal area of the teeth is difficult to keep clean, thus resulting in a higher incidence of caries forming. Occlusal surfaces are susceptible to caries because of poorly coalesced pits and fissures. Lingual surface is smooth and easier to keep clean. Not all options listed are correct. Only A and B are correct.

DIF: Knowledge REF: p. 1 OBJ: 2 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 3.0 Planning and Managing Dental Hygiene Care, 3.3.2.1 Dental Caries 28. Which of the following tissues is most likely to be affected by periodontal disease caused by

bacterial plaque? a. Periodontal ligament b. Enamel c. Dentin d. Pulp ANS: A

A B

Feedback Unlike caries, periodontal disease affects the tissues supporting the teeth, including the gingiva, periodontal ligament, cementum, and alveolar bone. Enamel is not a supporting tissue of the teeth and therefore is not affected by periodontal disease. Dentin is not a supporting tissue of the teeth and therefore is not affected by periodontal disease. Pulp is not a supporting tissue of the teeth and therefore is not affected by periodontal disease.

DIF: Knowledge REF: p. 1 OBJ: 2 TOP: CDA, GC, V. A.1b. Patient Education and Oral Health Management MSC: NBDHE, 3.0 Planning and managing dental hygiene care, 3.3.2.1 Dental Caries 29. What is a significant cause of dental caries and periodontal disease in older adults? a. Diet b. Health c. Salivary flow d. Brushing habits ANS: C

Feedback Poor diet may contribute to caries formation and periodontal disease, but it requires additional factors to produce results. Poor health may contribute to caries formation and periodontal disease, but it requires additional factors to produce results.

Many older individuals experience decreased salivary production, which limits the body’s oral immune response and promotes both caries and periodontal disease.

Poor brushing habits may contribute to caries formation and periodontal disease but require additional factors to produce results.

DIF: Knowledge REF: p. 3 OBJ: 2 TOP: CDA, GC, V. A.1b. Patient Education and Oral Health Management MSC: NBDHE, 3.0 Planning and managing dental hygiene care, 3.3.2.1 Dental Caries 30. Of the following, which material would not be used for an intracoronal restoration? a. Amalgam b. Porcelain c. Composite resin ANS: B

A B

Feedback Cavity preparations may be restored with materials such as amalgam, resin composites, cast alloys, or ceramics, or less often by gold foil. Porcelain is an indirect placement material that is fabricated in the dental laboratory and cemented into place. Cavity preparations may be restored with materials such as amalgam, resin composites, cast alloys, or ceramics, or less often by gold foil.

DIF: Comprehension EF p.R. 4 COM OBJ: 3 TESTBANKSRE L:LE TOP: CDA, GC, III, B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam, c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 31. Which of the following would not be considered an extracoronal, or indirect placement,

restoration? a. Amalgam b. Veneer c. Crown d. Onlay ANS: A

B C D

Feedback Extracoronal restorations are not conservative preparations and require a material strong enough to cover and support the exterior surfaces of the tooth. Veneers are extracoronal restorations that are fabricated in the dental laboratory. Crowns are extracoronal restorations that are fabricated in the dental laboratory. Onlays are extracoronal restorations that are fabricated in the dental laboratory.

DIF: Knowledge REF: p. 5 OBJ: 3 TOP: CDA, GC, III, B, 1, Describe how to prepare, mix, deliver, and store restorative materials,

including but not limited to a. amalgam, c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 32. How would a permanent three-unit bridge be classified? a. Indirect restoration b. Direct restoration c. Intracoronal d. Extracoronal e. Both A and D are correct. ANS: E

B C

Feedback A permanent three-unit bridge is made outside of the mouth; therefore it is an indirect restoration. A direct restoration is placed directly into the tooth at the time of preparation. An intracoronal restoration is placed directly into the tooth either by way of an immediate restorative material or a cemented direct restoration. A permanent three-unit bridge, is comprised of extracoronal restorations soldered together into a single unit. Answers A and D are both correct.

DIF: Comprehension REF: p. 11 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 33. How would a composite resin restoration be classified? a. Direct restoration b. Indirect restoration c. Intracoronal restoration d. Extracoronal restoration e. Both A and C ANS: E

A B C D

Feedback A composite resin restoration is placed directly into the mouth. An indirect restoration is fabricated in the dental laboratory. A composite resin restoration is placed intracoronally. An extracoronal restoration covers the outside surfaces of a tooth and is cemented into place. Both A and C are correct.

DIF: Comprehension REF: p. 10 OBJ: 5 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 34. Endosseous dental implants rely on which method to retain them permanently? a. Osseointegration b. Bone graft c. Resin cement d. Pins or posts e. Both A and B ANS: E

C D

Feedback Osseointegration is the process whereby new bone grows in and around the implant to retain it in place. A bone graft might be used prior to the implant being prepared and placed when there is not enough natural bone to retain the implant. Resin cement is not a viable option. Pins and posts are used to retain intraoral and extraoral restorations when not enough tooth structure remains. Both A and B are correct.

DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 35. Of the following, which is not an advantage of finishing and polishing a restoration? a. Minimized stain b. Minimized corrosion c. Minimized recurrent caries d. Minimized plaque retention ANS: D

A B C D

Feedback The statement is an advantage. The statement is an advantage. The statement is an advantage. Restoration also may be polished to minimize plaque retention and corrosion, and other abrasives may be used to finish the edges (margins) of the restoration to help prevent the recurrence of caries, but staining will not be minimized.

DIF: Comprehension REF: p. 12 OBJ: 6 TOP: CDA, GC, III.D.1. Select and describe how to manipulate the various finishing, polishing and cleaning agents MSC: NBDHE, 5.0 Using preventive agents, 5.1.2 Toxicology

36. Fluoride are commonly used to deliver fluoride to an area prepared for restoration. a. gels b. rinses c. varnishes d. filling materials ANS: C

Feedback Fluoride gels are highly effective at preventing caries through topical applications. Fluoride rinses are highly effective at preventing caries through topical applications. Fluoride gels, rinses, and varnishes are highly effective at preventing caries. Fluorides also have been incorporated into direct esthetic filling materials and cements. Fluoride varnishes are highly effective at preventing caries through topical applications.

DIF: Comprehension REF: p. 47 OBJ: 6 TOP: CDA, GC, III.B.1. Describe how to prepare, mix, deliver, and store restorative materials MSC: NBDHE, 5.0 Using preventive agents, 5.1.1 Mechanisms of action SHORT ANSWER 1. Compare and contrast intraTcE orS onTaBl A reN stK orSatEioLnL sE wR ith.C exOtrM acoronal restorations. ANS:

Intracoronal restorations are used to repair damage that is restricted to the internal parts of the tooth. Extracoronal restorations are used if the damage to the tooth is extensive, because they extend beyond the interior of the tooth to cover the cusp tips and other external surfaces. DIF: Analysis REF: pp. 4-5 OBJ: 3 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge preparation/cementation MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Identify an advantage to a patient who wears a partial denture. ANS:

Removable partial dentures are advantageous to the patient from the standpoint of cleaning and inspection of the remaining teeth. DIF: Knowledge REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to e. crown and bridge preparation/cementation MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

3. Discuss the role of dental materials in treating trauma-related tooth injuries. ANS:

Restorative materials are used to repair teeth, stabilize them until the supporting tissues heal, or replace them. DIF: Comprehension REF: p. 12 OBJ: 5 TOP: CDA, GC, II. B.2. e. Select and describe how to prepare tray setups and all necessary armamentaria for chairside dentistry and dental emergency procedures, including but not limited to cc. temporary restoration MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. Describe the purpose of mouth protectors. ANS:

Mouth protectors are made of polymers that absorb the energy of facial blows and prevent this energy from affecting the teeth and facial structures. DIF: Comprehension REF: p. 12 OBJ: 6 TOP: CDA, GC, IV. B. 3. Laboratory materials and procedures MSC: NBDHE, 5.0 Using Preventive Agents, 5.3 Other preventive agents

Chapter 02: Properties of Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. For which of the following materials do dimensional changes occur during setting as a result

of a chemical reaction? a. Elastomeric impression materials b. Gold restorations c. Wax patterns d. A and C e. B and C ANS: A

B C D E

Feedback Dimensional changes occur during setting as a result of a chemical reaction with elastomeric impression materials. Resin composite materials also set as a result of a chemical reaction and undergo shrinkage. Gold restorations undergo dimensional changes from cooling during fabrication. Wax patterns undergo dimensional changes from cooling during fabrication. A and C are incorrect answers. B is an incorrect answer, and C is an incorrect answer.

DIF: Comprehension REF: p. 15 OBJ: 1 TOP: CDA, GC, III. ChairsiTdE eD SeTnB taA lM NaKteSriEalL sL (PE reR pa.raCtiO onM, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 2. How is the percentage of dimensional change measured? a. An original length or volume b. The final length or volume c. The compressive strength d. The tensile strength e. The shear strength ANS: A

A B C D E

Feedback The dimensional change usually is expressed as a percentage of an original length or volume, not the final length or volume. The dimensional change usually is expressed as a percentage of an original length or volume, not the final length or volume. Compressive strength is a measure of stress that may result when force is applied to a material. Tensile strength is a measure of stress that may result when force is applied to a material. Shear strength is a measure of stress that may result when force is applied to a material.

DIF: Knowledge REF: p. 15 OBJ: 1 TOP: CDA, GC, III. Chairside Dental Materials (Preparation, Manipulation and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 3. The volumetric dimensional change is equal to a. two b. three c. four d. six

times the linear dimensional change.

ANS: B

A B

C D

Feedback Two is an incorrect answer. The volumetric dimensional change is equal to three times the linear dimensional change. Volume is described as length times width times depth (or height). Four is an incorrect answer. Six is an incorrect answer.

DIF: Knowledge REF: p. 15 OBJ: 1 TOP: CDA, GC, III. Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials

ER 4. Because the thermal expanT siE onST ofBaArN esK toSraEtiL veLm at. erC iaO lM usually does not match that of the tooth structure, a differential expansion or contraction occurs that may result in leakage of oral fluids between the restoration and tooth. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct.

DIF: Comprehension REF: p. 15 OBJ: 2 TOP: CDA, GC, III. Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 5. A new addition silicone impression material is tested for linear dimensional change upon

setting. The result of –0.34% indicates that after setting.

took place within 24 hours

a. b. c. d.

linear expansion linear shrinkage thermal expansion thermal shrinkage

ANS: B

A B C D

Feedback Linear thermal expansion is expressed as a coefficient of thermal expansion. The result is a negative number, which indicates shrinkage took place. Thermal expansion is measured by determination of the difference in the length of a specimen at two temperatures. Shrinkage is measured by determination of the difference in the length of a specimen at two temperatures.

DIF: Knowledge REF: p. 15 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 6. The thermal coefficient of expansion

and is usually a. is; lower b. is; higher c. is not; lower d. is not; higher

uniform throughout the entire temperature range for liquids than solids.

ANS: D

A B C D

Feedback The thermal coefficient of expansion for a solid generally increases at some point as the temperature is increased. The thermal coefficient of expansion for a solid generally increases at some point as the temperature is increased. The thermal coefficient of expansion for a solid generally increases at some point as the temperature is increased. The thermal coefficient of expansion is not uniform throughout the entire temperature range and is usually higher for liquids than solids.

DIF: Comprehension REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 7. Which of the following restorative materials has a linear thermal coefficient of expansion that

is lower than that of human teeth? a. Ceramics b. Composites c. Dental amalgam d. Unfilled acrylics and sealants

ANS: A

A B C D

Feedback Ceramics have a linear thermal coefficient of expansion of 14. Teeth have a linear thermal coefficient of expansion of 15. The linear thermal coefficient of expansion of composites is 68. The linear thermal coefficient of expansion of dental amalgam is 28. The linear thermal coefficient of expansion of unfilled acrylics and sealants is 100.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 8. Which of the following dental restorative materials has a linear coefficient of thermal

expansion closest to teeth? a. Unfilled acrylics and sealants b. Glass ionomer base c. Dental amalgam d. Composites e. Gold alloys ANS: A

A B C D E

Feedback Unfilled acrylics and T seEalSanTtB s ha eS aE linLeL arEcR oe.fC ficOiM ent of thermal expansion of ANvK 70-100. Glass ionomer base has a linear coefficient of thermal expansion of 10-11. Dental amalgam has a linear coefficient of thermal expansion of 22-28. Composites have a linear coefficient of thermal expansion of 25-68. Gold alloys have a linear coefficient of thermal expansion that is closest to teeth.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 9. What occurs as the result of a discrepancy between the linear thermal coefficient of expansion

between teeth and the restorative material if there is no bonding? a. Stress b. Strain c. Percolation d. Yield strength e. Elastic modulus ANS: D

Feedback If the restoration is bonded, then stress occurs at the interface of the tooth and

B C

D E

restoration. Strain occurs as result of the change in length or deformation by unit. Percolation occurs as the result of a discrepancy between the linear thermal coefficient of expansion between teeth and the restorative material. It is thought to be undesirable due to possible irritation to the dental pulp and recurrent decay. Yield strength is affected by stress at some arbitrary value. Elastic modulus equals the ratio of stress to strain.

DIF: Knowledge REF: p. 20 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 10. Percolation is thought to decrease with time following insertion of which of the following

dental restorative materials? a. Filled resin composite b. Unfilled acrylic resin c. Dental amalgam d. Cast gold e. Ceramic ANS: D

C D

Feedback Filled resin composite is restoration that is either bonded or cemented into place. Percolation related to these restorations would place stress at the interface, which over time would lead T toEfS aiT luBreAoNfKthSeEbL onLdE . R.COM Unfilled acrylic resin is restoration that is either bonded or cemented into place. Percolation related to these restorations would place stress at the interface, which over time would lead to failure of the bond. Percolation is thought to decrease with time with dental amalgam, presumably as a result of the space being filled with corrosion products from the amalgam. Cast gold is restoration that is either bonded or cemented into place. Percolation related to these restorations would place stress at the interface, which over time would lead to failure of the bond. Ceramic is restoration that is either bonded or cemented into place. Percolation related to these restorations would place stress at the interface, which over time would lead to failure of the bond.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 11. What is used as a measurement of heat transfer? a. Linear coefficient of thermal expansion b. Thermal conductivity c. Galvanism d. Absorption e. Adsorption

ANS: B

A B C D E

Feedback Linear coefficient of thermal expansion is determined by the length of a specimen at two temperatures. Thermal conductivity is used as a measure of heat transferred. Galvanism is the generation of an electric current a patient can feel. Absorption refers to uptake of liquid. Adsorption refers to concentration of molecules at the surface of a solid or liquid.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 12. Which of the following dental restorative materials has the greatest thermal conductivity? a. Resin composites b. Unfilled acrylics c. Dental amalgam d. Gold alloys e. Ceramic ANS: D

A B C D E

Feedback OpMarable to tooth structure. Resin composites havT eE thSerTmBaA l cNoK nS duEcL tivLitEieRs .coCm Unfilled acrylics have lower thermal conductivity than enamel. The thermal conductivity of dental amalgam is substantially lower than gold. Gold alloys have the greatest thermal conductivity. Ceramic has thermal conductivity comparable to tooth structure.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 13. Which of the following dental materials has a thermal conductivity that is most similar to

tooth structure? a. Composites b. Gold alloys c. Dental amalgam d. Zinc phosphate cement e. Zinc oxide–eugenol cement ANS: B

A B

Feedback Composites have thermal conductivity most similar to tooth structure. Gold alloys have thermal conductivity higher than tooth structure.

C D E

Dental amalgam has some thermal conductivity but not at a level similar to tooth structure. Zinc phosphate cement is a poor conductor of temperature and is used for insulating bases. Zinc oxide–eugenol cement is a poor conductor of temperature and is used for insulating bases.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 14. Why are cavity varnishes and liners ineffective as thermal insulators? a. Used in thin layers b. High thermal conductivity c. Low coefficient of thermal expansion d. High coefficient of thermal expansion ANS: A

A B C D

Feedback Cavity varnishes and liners have low thermal conductivities but are used in layers so thin that they are ineffective as thermal insulators. Varnishes and liners have low thermal conductivity. Low coefficient of thermal expansion is a measurement of how much a material expands. High coefficient of thT erE mSaT l eBxA paNnK siS onEiL sL aE mR ea.sC urOem M ent of how much a material expands.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 15. Which of the following is an electrical property of interest in the mouth? a. Coefficient of thermal expansion b. Elastic modulus c. Percolation d. Galvanism e. Ductility ANS: D

A B C D

Feedback Coefficient of thermal expansion measures how much a material expands. Elastic modulus is equal to the ratio of stress to strain in the liner portion of the stress-strain curve. Percolation occurs as the result of a discrepancy between the linear thermal coefficient of expansion between teeth and the restorative material. Galvanism is an electrical property. Galvanism results from the presence of

dissimilar metals in the mouth. Metals placed in an electrolyte have various inherent tendencies to go into solution. Ductility is the percent of elongation.

DIF: Knowledge REF: p. 17 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 16. Given a schematic sketch of two opposing teeth, one with a temporary aluminum alloy crown

and the other with a gold crown, which one would be the electrolyte? a. Saliva b. Gold crown c. Difference in electrical potential d. Temporary aluminum alloy crown ANS: A

A B C D

Feedback The saliva functions as the electrolyte. Gold crown does not go into solution. The difference in electrical potential in this case would be 2.69 volts. The patient experiences pain and a metallic taste. Temporary aluminum alloy crown has a tendency to go into solution.

DIF: Knowledge REF: p. 17 OBJ: 2 TOP: CDA, GC, III ChairsiT deEDSeT ntB alAMNaK teS riaElsL(L PrE epRa. raC tioOnM , Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 17. What refers to the uptake of liquid by a bulk solid? a. Absorption b. Adsorption c. Hydrophilic d. Hydrophobic ANS: A

A B C D

Feedback Absorption refers to the uptake of liquid by a bulk solid. Adsorption indicates concentration of molecules at the surface of a solid or liquid. Hydrophilic surface is readily wetted if the solution is water. Hydrophobic surface is resistant to wetting if the solution is water.

18. Which of the following terms indicates concentration of molecules at the surface of a solid or

liquid? a. Corrosion b. Adsorption c. Absorption d. Hydrophilic ANS: B

A B C D

Feedback Corrosion is the dissolution of metals in the mouth. Adsorption indicates concentration of molecules at the surface of a solid or liquid. Absorption is the uptake of liquid by a bulk solid. Hydrophilic surface is readily wetted if the solution is water.

DIF: Knowledge REF: p. 17 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 19. With regard to wettability and water, what does a low contact angle indicate? a. The material is hydrophilic. b. The material is hydrophobic. c. The contact angle is greater than 90°. d. Both A and C are correct. e. Both B and C are correT ctE. STBANKSELLER.COM ANS: A

A B C D E

Feedback A low contact angle indicates the material is hydrophilic. If the contact angle is greater than 90°, poor wetting occurs. The material is considered hydrophobic if the liquid is water. A is correct, and C is incorrect. B and C are incorrect.

DIF: Comprehension REF: p. 18 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 20. Which of the following choices encourage good wetting? a. Low-energy solid b. High-energy solid c. High-energy liquid d. A and C are correct. e. B and C are correct. ANS: A

A B C D E

Feedback Liquids bead up on low-energy solids. High-energy solids and low-energy liquids encourage good wetting. High-energy liquids can be made more wettable by adding a wetting agent. A is correct, and C is incorrect. B and C are incorrect.

DIF: Comprehension REF: p. 18 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 21. On which teeth are the greatest biting forces located? a. Molars b. Canines c. Incisors d. Premolars ANS: A

A B C D

Feedback The greatest biting forces are on molars. Canines’ maximum biting forces decrease from the molar to the incisor region. Premolars’ maximum biting forces decrease from the molar to the incisor region. Incisors’ maximum biting forces decrease from the molar to the incisor region.

DIF: Knowledge REF: TpE . S1T 8 BANKS OE BL J:LE 5 R.COM TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 22. Patients with dentures can apply about a. 10 b. 19 c. 50 d. 90 e. 150

% of the force of those with normal dentition.

ANS: B

A B C D E

Feedback Patients with dentures can apply about 19% of the force of those with normal dentition. Patients with dentures can apply about 19% of the force of those with normal dentition. Patients with dentures can apply about 19% of the force of those with normal dentition. Patients with dentures can apply about 19% of the force of those with normal dentition. Patients with dentures can apply about 19% of the force of those with normal

dentition. DIF: Knowledge REF: p. 18 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 23. What is the ratio of the force to the area called? a. Stress b. Strain c. Tensile strength d. Elastic modulus ANS: A

A B C D

Feedback The ratio of the force to the area is called stress. Strain changes in length per unit of a material produced by stress. Tensile strength results when a material fractures from tensile stress. Elastic modulus is equal to the ratio of the stress to the strain.

DIF: Knowledge REF: p. 18 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 24. For a given force, the

stress. a. smaller; smaller b. smaller; larger c. larger; larger d. A and C e. B and C

e area over which it is applied, the TEStThB ANKSELLER.COM

the value of the

ANS: B

A B C D E

Feedback The smaller the area over which force is applied, the larger the value of stress. The smaller the area over which force is applied, the larger the value of stress. The smaller the area over which force is applied, the larger the value of stress. The smaller the area over which force is applied, the larger the value of stress. The smaller the area over which force is applied, the larger the value of stress.

DIF: Comprehension REF: p. 18 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 25. Which of the following statements is true of the proportional limit? a. Below the proportional limit a material is plastic, and above the proportional limit

it is elastic.

b. Below the proportional limit a material is elastic, and above the proportional limit

it is plastic. c. A material is elastic both below and above the proportional limit. d. A material is plastic both below and above the proportional limit. ANS: B

A B C D

Feedback A restoration can be classified as a clinical failure if deformation occurs beyond set limits. Below the proportional limit a material is elastic, and above the proportional limit it is plastic. A restoration can be classified as a clinical failure if deformation occurs beyond set limits. A restoration can be classified as a clinical failure if deformation occurs beyond set limits.

DIF: Knowledge REF: p. 20 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 26. Which of the following statements is true of the tensile and compressive strengths of a

material? a. They may be significantly different. b. Brittle materials are stronger in tension than in compression. c. Brittle materials have sT mEaS ll T diB ffA erNenKcSesEiL nLteEnR si. leCaO ndMcompressive strength. d. A, B, and C are true. e. A and C are true. ANS: A

A B C D E

Feedback The tensile and compressive strength of a material may be significantly different. Brittle materials such as human enamel, amalgam, and composites have large differences and are stronger in compression than in tension. Brittle materials such as human enamel, amalgam, and composites have large differences and are stronger in compression than in tension. Brittle materials such as human enamel, amalgam, and composites have large differences and are stronger in compression than in tension. Brittle materials such as human enamel, amalgam, and composites have large differences and are stronger in compression than in tension.

DIF: Comprehension REF: p. 20 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 27. “Measures the energy required to fracture a material” is the definition of which term? a. Ductility

b. Resilience c. Toughness d. Malleability ANS: C

A B C D

Feedback Ductility is the percent of elongation. Resilience is the energy required to deform a material. The energy required to fracture a material is a measure of its toughness. Malleability is the percent of compression.

DIF: Analysis REF: p. 21 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 28. Which of the following statements is true of the measure of Knoop hardness? a. It is obtained by measurement of the short diagonal of an indentation from a

diamond indenter. b. Enamel has a lower Knoop hardness value than dentin and cementum. c. Hardness is directly related to yield strength and wear resistance. d. The larger the indentation, the smaller the value. ANS: D

A B C D

Feedback In general, no direct rT elE atS ioTnsBhA ipNeKxS isE tsLbL etE wR ee.nChO arMdness and yield strength and wear resistance. Enamel has a higher Knoop hardness value than dentin and cementum. In general, no direct relationship exists between hardness and yield strength and wear resistance. The larger the indentation of the measurement of the long diagonal from a diamond indenter, the smaller the Knoop hardness value.

DIF: Analysis REF: p. 21 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 29. Analysis of the strain–time curve indicates that the

the time and the force applied to the impression material, the lower the permanent strain and the more accurate the impression. a. shorter; less b. longer; less c. shorter; more d. longer; more ANS: A

Feedback

A B C D

The shorter the time and the less force applied to the impression material, the lower the permanent strain and the more accurate the impression. Longer time will result in more force to the material. Shorter time will result in less force to the material. Longer time will result in more force to the material and compromise the accuracy of the impression.

DIF: Analysis REF: p. 22 OBJ: 9 TOP: CDA, GC, V. A.1b. Patient Education and Oral Health Management MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 30. Dimensional change may occur during setting as a result of which factor? a. Volumetric change b. Chemical reaction c. Cooling d. All of the above e. B and C are correct. ANS: E

A B C D E

Feedback Volumetric change is more difficult to measure. B and C are correct answers. B and C are correct answers. B and C are correct answers. Dimensional changesTmEaS yT ocBcA urNdKuS riE ngLsLeE ttiR ng.C asOaMresult of a chemical reaction, such as with elastomeric impression materials or resin composite restorative materials, or from the cooling of wax patterns or gold restorations during fabrication.

DIF: Comprehension REF: p. 15 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 31. Expansion and contraction rates between dental materials and tooth structure caused by

temperature change vary. Gaps at the margins allow fluids to enter the space. What is this known as? a. Coefficient of thermal expansion b. Thermal conductivity c. Dimensional change d. Percolation ANS: D

A B

Feedback Coefficient of thermal expansion is expressed as the linear difference of a specimen at two temperatures. Thermal conductivity is used to measure heat transference.

C D

Dimensional change is expressed as a percent of the original length. Small gaps result at the junction between the two materials. Oral fluids can penetrate this space. When the temperature returns to normal, this fluid is forced out of the space. This phenomenon is called percolation.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 32. Of the following materials, which has the closest coefficient of expansion to tooth structure? a. Ceramic b. Amalgam c. Filled polymers d. Composite resins ANS: A

A B C D

Feedback Ceramic is the closest, being one half to one third, and gold alloys being approximately the same as for human teeth. Values for amalgam and composites are about two to five times those of human teeth. Values for unfilled polymers, however, are five to seven times those of teeth. Values for amalgam and composites are about two to five times those of human teeth.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 33. Which of the following materials has the highest rating related to thermal conductivity? a. Glass ionomer b. Gold alloy c. Enamel d. Dentin ANS: B

A B C D

Feedback Glass ionomer cement bases closely replace lost tooth structure with respect to thermal conductivity. Human enamel and dentin are poor thermal conductors compared with gold alloys and dental amalgam, although amalgam is substantially lower than gold. Human enamel and dentin are poor thermal conductors. Human enamel and dentin are poor thermal conductors.

DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application)

MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 34. What causes corrosion? a. Contact of two dissimilar metals in the mouth b. Poor oral hygiene around restorations c. Acidic food and drink d. A and C are correct. ANS: D

A B C D

Feedback A and C are correct. Poor oral hygiene around restorations may result in recurrent caries formation. Corrosion also may result from chemical attack of metals by components in food or saliva. Corrosion also can result from this same condition when adjacent restorations are of dissimilar metals. Corrosion may also be a factor due to chemical attacks for food and saliva in the mouth.

DIF: Knowledge REF: p. 17 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 35. Which term refers to the cause of a metallic taste in the mouth? a. Corrosion b. Galvanism c. Percolation d. Contamination ANS: B

A B

Feedback Corrosion is a result of the same condition. As a result of the galvanic action, material goes into solution, and roughness and pitting occur. When the two restorations touch, current flows because the potential difference is 2.69 volts, and the patient experiences pain and frequently complains of a metallic taste. Small gaps result at the junction between the two materials. Oral fluids can penetrate this space. When the temperature returns to normal, this fluid is forced out of the space. This phenomenon is called percolation. Corrosion may occur if a gold alloy is contaminated with a metal such as iron during handling in the dental laboratory.

DIF: Knowledge REF: p. 17 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 36. What is a material called if a liquid presents a contact angle of wettability greater than 90°?

a. b. c. d.

Viscous Thixotropic Hydrophilic Hydrophobic

ANS: C

A B C D

Feedback Viscosity is related to the thickness of a material and may be affected by temperature. Thixotropic materials require force to be distributed. Hydrophilic materials flow readily. If a contact angle is greater than 90°, poor wetting occurs (hydrophobic if the liquid is water).

DIF: Knowledge REF: p. 18 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 37. Which of the following is not a form of stress? a. Compressive b. Flexure c. Strain d. Shear ANS: C

A B C D

Feedback Compressive is a type of stress that may result when a force is applied to a material. Flexure is a type of stress that may result when a force is applied to a material. Strain is the change in length per unit length of a material produced by stress. Shear is a type of stress that may result when a force is applied to a material.

DIF: Knowledge REF: p. 19 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 38. Which term refers to the change in the length or deformation of a material when subjected to

force? a. Flexure b. Tensile c. Strain d. Shear ANS: C

Feedback Flexure is a type of stress.

B C D

Tensile is a type of stress. Strain is the change in length or deformation per unit length when a material is subjected to a force. Shear is a type of stress.

DIF: Knowledge REF: p. 19 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 39. When a material reaches its a. stress-strain curve b. ultimate strength c. elastic modulus d. yield strength

, deformation of a material becomes permanent.

ANS: D

A B C D

Feedback Stress–strain curve is the application of various forces to determine the corresponding values of stress and strain. Ultimate strength is the stress at which fracture occurs. Elastic modulus is equal to the ratio of the stress to the strain. Yield strength is the measure of the stress allowed before permanent deformation.

DIF: Knowledge REF: TpE . S2T 0 BANKS OE BJ:LLE 6 R.COM TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 40. How is the hardness of a dental material reported? a. Knoop hardness b. Nano-indentation c. Diamond indenter d. Dynamic properties ANS: A

A B C D

Feedback The hardness of dental materials generally is reported in Knoop hardness. Nano-indentation measures small indentations from small loads. Diamond indenter creates a length of the long diagonal of an indentation. Dynamic properties occur at extremely high rates of loading such as an impact.

DIF: Knowledge REF: p. 21 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 41. What is the energy it takes to deform a material called?

a. b. c. d.

Relationship Resistance Resilience Rebound

ANS: C

A B C D

Feedback Relationship is a distractor. Resistance is a material’s ability to stay the same. The energy required to deform a material permanently is a criterion of its resilience. Rebound is a material’s ability to return to its original form.

DIF: Knowledge REF: p. 21 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 42. What is the energy necessary to fracture called? a. Yield strength b. Toughness c. Stress d. Strain ANS: B

B C D

Feedback The yield strength is the stress at some arbitrarily selected value of permanent strain, such as 0.001, and thus is always slightly higher than the proportional limit. The energy necessary to fracture a material is a measure of its toughness. When force is distributed over an area, the ratio of the force to the area is called the stress. Strain is the change in length per unit length of a material produced by stress.

DIF: Knowledge REF: p. 21 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials SHORT ANSWER 1. Detail the significance of thermal dimensional change. ANS:

Restorative dental materials are subjected to temperature changes in the mouth. These changes result in dimensional changes in the materials and to the neighboring tooth structure. Because the thermal expansion of the restorative material usually does not match that of the tooth structure, a differential expansion occurs that may result in leakage of oral fluids between the restoration and the tooth. DIF: Comprehension REF: p. 15 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 2. Compare and contrast the terms absorption and adsorption. ANS:

Absorption refers to the uptake of liquid by the bulk solid. For example, the equilibrium absorption of water by acrylic polymers is in the range of 2%. Adsorption indicates concentration of molecules at the surface of a solid or liquid. DIF: Analysis REF: p. 17 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 3. Explain the difference between ductility and malleability. ANS:

The percents of elongation and compression are important properties in that they are measures of ductility and malleabilitT y,ErS esT peBcA tivNeKlyS. E TL heLseEtRw.oCpO roMperties are indications of the amount of plastic strain or deformation that can occur before the material fractures and, as such, indicate the brittleness of the material. DIF: Comprehension REF: p. 21 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 4. What is the purpose of using dental cements as bases within a cavity preparation? ANS:

The reason for using cements as thermal insulating bases in deep cavity preparations is that although dentin is a poor thermal conductor, a thin layer of it does not provide enough thermal insulation for the pulp unless a cement base is used under the metal restoration. DIF: Knowledge REF: p. 16 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 5. Compare and contrast the processes of tarnish and corrosion. ANS:

Corrosion is the dissolution of metals in the mouth. Corrosion also can result from this same condition when adjacent restorations are of dissimilar metals. As a result of the galvanic action, material goes into solution, and roughness and pitting occur. Corrosion may also be a reaction to the acids formed by food remnants combining with saliva. Tarnish is a surface reaction of metals in the mouth from components in saliva or foods. Corrosion is destructive whereas tarnish is just unsightly. DIF: Analysis REF: p. 17 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials

Chapter 03: Preventive Dental Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Which of the following is considered to be a preventive dental material? a. Pit and fissure sealant b. Dental amalgam c. Ceramic veneer d. Full gold crown ANS: A

A B C D

Feedback Fluoride gels, pit and fissure sealants, and mouth protectors are considered to be preventive dental materials. Dental amalgam is considered to be a restorative dental material. Porcelain veneers are considered to be a restorative dental material. Full gold crowns are considered to be a restorative dental material.

DIF: Knowledge REF: p. 27 OBJ: 10 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants 2. Which type of fluoride treatment is best to use for a patient with dentinal hypersensitivity (has

a neutral pH)? a. Acidulated phosphate fluoride b. Stannous fluoride c. Sodium fluoride d. A and C e. B and C ANS: C

A B C D E

Feedback Acidulated phosphate does not have a neutral pH. Stannous fluorides have acidic values of pH. Sodium fluoride has a neutral pH. A is an incorrect answer. C is a correct answer B is an incorrect answer, and C is a correct answer.

DIF: Comprehension REF: p. 27 OBJ: 3 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 3. Which type of fluoride will not etch restorations?

a. b. c. d. e.

Acidulated phosphate fluoride Stannous fluoride Sodium fluoride A and B B and C

ANS: C

A B C D E

Feedback Acidulated phosphate fluorides can etch restorations. Stannous fluoride can etch restorations. Sodium fluoride will not etch restorations. A and B are incorrect answers. B is an incorrect answer, and C is a correct answer.

DIF: Comprehension REF: p. 28 OBJ: 2 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 4. Which type of fluoride can stain restorations? a. Sodium fluoride b. Stannous fluoride c. Acidulated phosphate fluoride TESTBANKSELLER.COM d. A, B, and C e. A and C ANS: B

A B C D E

Feedback Sodium fluoride does not stain restorations. Stannous fluoride can stain restorations. Acidulated phosphate fluoride does not stain restorations. A is the only correct choice. A is the only correct choice.

DIF: Comprehension REF: p. 28 OBJ: 2 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 5. What does thixotropic mean? a. Viscosity of the material is changeable. b. Material will adhere to an intraoral surface. c. Grain size of cast gold is affected by quenching.

d. Setting time of the material is affected by glove powder. ANS: A

B C D

Feedback Thixotropic means the viscosity of the material is changeable. Examples found in dentistry include one form of topical dental anesthetic. Yogurt is another example of a thixotropic material. The material does not have adhesive properties. Quenching is the process of rapidly cooling cast gold. There is no chemical or setting reaction involved.

DIF: Knowledge REF: p. 28 OBJ: 1 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 6. Fluoride varnishes are available that contain a. 1% sodium b. 5% sodium c. 1% stannous d. 5% stannous e. 2.34% acidulated phosphate-fluoride (APF)

fluoride.

ANS: B

A B C D E

Feedback 1% sodium is related to gel deliveries of acidulated phosphate fluoride. Fluoride varnishes are available that contain 5% sodium fluoride. Because it stains, 1% stannous is rarely used. Because it stains, 5% stannous is rarely used. 2.34% APF is related to gel deliveries of acidulated phosphate fluoride.

DIF: Knowledge REF: p. 28 OBJ: 1 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 7. Which of the following statements is true about 4-minute versus 1-minute application of a

fluoride treatment? A 4-minute application is a. not currently recommended. b. less effective than a 1-minute application. c. equally effective as a 1-minute application. d. more effective than a 1-minute application.

ANS: D

A B C D

Feedback A 4-minute application is necessary for full fluoride uptake. A 4-minute application is necessary for full fluoride uptake. A 4-minute application is necessary for full fluoride uptake. A 4-minute application appears to be more effective than a 1-minute application.

DIF: Knowledge REF: p. 28 OBJ: 3 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 8. Which of the following statements is true of the manipulation of fluoride foams and gels

during their application for office fluoride treatment? a. The troughs of the maxillary and mandibular trays should be completely filled with the gel. b. The teeth are to be kept as free from saliva as possible before application of the tray. c. After application of the gel, the patient is instructed not to eat for 4 hours. d. Rinses are recommended for children under 6 years old. e. They should be applied prior to dental prophylaxis. ANS: B

A B C D E

Feedback A ribbon of gel should be placed in the troughs of the maxillary and mandibular trays. The teeth are to be kept as free from saliva as possible before application of the tray during the application of office fluoride treatments. After application of the gel, the patient is instructed not to eat for 30 minutes. Rinses are not recommended for children under 6 years old. They should be applied after rather than before dental prophylaxis.

DIF: Analysis REF: p. 28 OBJ: 2 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage. MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.3 Methods of administration 9. Application of fluoride is least effective in preventing caries on which of the following

surfaces of posterior teeth? a. Distal b. Mesial c. Buccal

d. Lingual e. Occlusal ANS: E

A B C D E

Feedback Distal involves smooth surfaces where fluoride is most effective. Mesial involves smooth surfaces where fluoride is most effective. Buccal involves smooth surfaces where fluoride is most effective. Lingual involves smooth surfaces where fluoride is most effective. Application of fluoride is least effective in pits and fissures as a result of the special anatomy of the occlusal surfaces of posterior teeth.

Which of the following statements is true about pits and fissures? A smooth-based depression on the occlusal surface of a tooth. The result of noncoalescence of dentin during tooth formation. The result of noncoalescence of enamel during tooth formation. May be cleansed by the excursion of food or a toothbrush bristle.

a. b. c. d.

ANS: C

A B C

Feedback Pits and fissures are narrow, deep depressions. It may extend as far as the dentoenamel junction. The pit and fissure is an enamel fault that is the result of noncoalescence of enamel during tooth formation. The noncoalescence may extend to the dentoenamel junction, or it may be incomplete. Pits and fissures may be very narrow, smaller than a single toothbrush bristle.

DIF: Comprehension REF: p. 28 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 11. Approximately a. 11 b. 24 c. 49 d. 74 e. 84

% of dental caries in children 5 to 17 years of age involves pits.

ANS: E

A B C D E

Feedback Eleven is a low random distracter. Twenty-four is a low random distracter. Forty-nine is low random distracter. Seventy-four is a low random distracter. Approximately 84% of dental caries in children 5 to 17 years of age involve pits.

DIF: Knowledge REF: p. 29 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 12. Pit and fissure sealants may be used to prevent caries in a. deciduous but not permanent b. permanent but not deciduous c. both deciduous and permanent d. neither deciduous nor permanent

teeth.

ANS: C

A B C D

Feedback This option is incorrect based on the answers of both. This option is incorreT ctEbS asTedBA onNtK heSaEnL sw otM h. LeErsRo.fCbO Pit and fissure sealants may be used to prevent caries in both deciduous and permanent teeth. This option is incorrect based on the answers of both.

DIF: Comprehension REF: p. 29 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 13. A preventive resin restoration involves the use of a. flowable composite b. hybrid ionomer c. glass ionomer d. compomer e. ceramic

to restore the teeth.

ANS: A

A B

Feedback A preventive resin restoration involves the use of flowable composite to restore the teeth. Hybrid ionomer is a thick material with little to no flow

C D E

Glass ionomer is a thick material with little to no flow. Compomer is a thick material with little to no flow. Ceramic is used for indirect restorations only.

DIF: Knowledge REF: p. 29 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants. MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 14. Which of the following materials is the chemistry of sealants most similar to? a. Composite restorative material b. Acidulated phosphate-fluoride c. Ceramic restorative material d. Glass ionomer cement ANS: B

A B

C D

Feedback APF is a fluoride. The chemistry of sealants is similar to composite restorative material. Sealants have fewer filler particles and are more fluid in order to penetrate pits and fissures in addition to the etched areas produced on the enamel. Ceramic is an indirect restorative material. Glass ionomer is a cement with a fluoride ion.

9 BANKS OE BL J:LE 7 R.COM DIF: Knowledge REF: TpE . S2T TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 15. Sealants polymerized by visible light are

-component systems that

require

mixing. a. one; do b. one; do not c. two; do d. two; do not ANS: B

A B C D

Feedback A one-component system does not require mixing. Sealants polymerized by visible light are one-component systems that do not require mixing. Sealants that self-cure are two-component systems that do require mixing. Sealants that self-cure are two-component systems that do require mixing.

DIF: Comprehension REF: p. 30 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e.

pit and fissure sealants. MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 16. What is the purpose of benzoyl peroxide in sealant materials? a. Monomer b. Inorganic filler c. Initiator of a two-component sealant system d. Initiator of a one-component sealant system e. Organic amine accelerator of a one-component sealant system ANS: C

A B C D E

Feedback Monomer is only present in a one-component system. Inorganic material is present in one- and two-component systems. Benzoyl peroxide is the initiator of a two-component sealant system. Diketone is the initiator in a one-component system. Organic amine accelerator is present in one- and two-component systems.

DIF: Knowledge REF: p. 30 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 17. How does acid etching of the enamel surface improve the retention of a sealant? a. Decreases the surface area b. Cleans the area to be sealed c. Improves the wettability of the enamel d. A, B, and C are all correct. e. Only B and C are correct. ANS: E

A B C D E

Feedback Acid etching increases the surface area. B and C are correct. B and C are correct. Only B and C are correct. Acid etching of the enamel surface improves the retention of sealant by cleaning the area to be sealed, improving the wettability of the enamel, increasing the surface area, and forming spaces into which the sealant can penetrate to form tags.

DIF: Comprehension REF: p. 30 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action

18. What did the results of a 5-year clinical study about sealant effectiveness, after a single

application of a pit and fissure sealant, indicate? a. Increased b. Decreased c. Remained unchanged d. Was tied to oral hygiene ANS: B

A B C D

Feedback The clinical study found the effectiveness of a single application of a sealant clearly decreases with time. The clinical study found the effectiveness of a single application of a sealant clearly decreases with time. The clinical study found the effectiveness of a single application of a sealant clearly decreases with time. Caution is warranted in comparison of some of these studies, because materials, techniques, teeth studied, and clinical criteria for judging success or failure vary from study to study.

DIF: Comprehension REF: p. 30 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 19. Current evidence indicatesTthEaS tT seB alA anNtsKsShE ouLldLE noRt . beCuOsM ed on the teeth of which type of

patient? a. Cooperates in maintaining good oral hygiene b. Has pits and fissures on occlusal surfaces c. Has been free of caries for several years d. Has no proximal lesions ANS: C

A B C D

Feedback Sealants also should not be used on the teeth of a patient who does not cooperate in maintaining good oral hygiene. Sealants should be used on occlusal surfaces where pits and fissures exist. Current evidence indicates that sealants should not be used on the teeth of a patient who has been free of caries for several years. Sealants should not be used on teeth with many proximal lesions.

DIF: Knowledge REF: p. 30 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 20. Etchants are generally a. hydrochloric

acid.

b. phosphoric c. salicylic d. acetic ANS: B

A B C D

Feedback Hydrochloric acid is not used to etch enamel. Etchants are generally 37% solutions of phosphoric acid in water. Salicylic acid is not used to etch enamel. Acetic acid is not used to etch enamel.

DIF: Knowledge REF: p. 32 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 21. Which of the following statements is true regarding placement of a sealant? a. If an etched tooth becomes contaminated with saliva, the etching and rinsing steps

need not be repeated. b. The self-cured sealant is cured with a light source for at least 20 seconds. c. Moisture enhances retention of the sealant by the fissure. d. A small cotton pellet may be used to remove sealant that has failed to polymerize

because of exposure to air. e. If a fluoride treatment is used in conjunction with the pit and fissure sealant, the fluoride treatment is apTpE lieSdTbBefAoN reKthSeEsL eaLlaEnR t ha .Cs Opolymerized. M ANS: D

A B C D E

Feedback The area must be re-etched and dried again. Self-cured sealant does not require a light to cure. Moisture inhibits retention of the sealant. If an etched tooth becomes contaminated with saliva, the etching and rinsing steps are repeated. If a fluoride treatment is used in conjunction with the pit and fissure sealant, the treatment is applied after the sealant has polymerized.

DIF: Analysis REF: p. 32 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.2 Techniques for application 22. Surveys report that orofacial injuries most frequently occur in which sport when the athlete is

not wearing a mouth protector? a. Basketball b. Football c. Hockey

d. Skiing e. Golf ANS: A

D E

Feedback Orofacial injuries most commonly occur in basketball, baseball, and soccer. Most injuries occur when the athlete does not wear a mouth protector. The Centers for Disease Control and Prevention (CDC) recommends that all players of contact sports use mouth protectors. The CDC found that football players do not sustain as many orofacial injuries as other athletes do because of required faceguards and mouth protectors. Most junior colleges and many amateur hockey and football leagues have adopted the rule mandated by the National Football Alliance Rules Committee that all high school athletes be equipped with internal mouth protectors. The CDC found that hockey players do not sustain as many orofacial injuries as other athletes do because of required faceguards and mouth protectors. Most junior colleges and many amateur hockey and football leagues have adopted the rule mandated by the National Football Alliance Rules Committee that all high school athletes be equipped with internal mouth protectors. Skiers do not sustain as many orofacial injuries as other athletes. Golfers do not sustain as many orofacial injuries as other athletes.

DIF: Knowledge REF: p. 33 OBJ: 14 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: TNE BS DT HB E,A5N .0KUSsiE ngLpLrE evR en.tiC veOaMgents, 5.3 Other preventive agents 23. Which statement(s) is/are true of custom-made mouth protectors? a. Athletes prefer the custom-made mouth protector over mouth-formed and stock

mouth protectors. b. Custom-made mouth protectors are less expensive than mouth-formed or stock

mouth protectors. c. Custom-made mouth protectors are less likely to interfere with speech than mouth-formed or stock mouth protectors. d. A and B are correct. e. A and C are correct. ANS: D

A B C D E

Feedback A and C are correct. Mouth protectors are more expensive than mouth-formed or stock mouth protectors. A and C are correct. A and C are correct. Athletes prefer the custom-made mouth protector over mouth-formed and stock mouth protectors; custom-made mouth protectors are more expensive than mouth-formed or stock mouth protectors; and custom-made mouth protectors are less likely to interfere with speech than mouth-formed or stock mouth protectors.

DIF: Comprehension REF: p. 33 OBJ: 17 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 24. A mouth protector thickness of

mm of material over incisal edges and cusps of teeth is recommended for best protection and acceptable comfort. a. 0.5 b. 1.0 c. 2.0 d. 4.0 e. 8.0 ANS: D

A B C D E

Feedback This answer provides insufficient thickness. This answer provides insufficient thickness. This answer provides insufficient thickness. A thickness of 4 mm of material over incisal edges and cusps of teeth is recommended for best protection and acceptable comfort. This answer provides excessive thickness.

DIF: Application REF: p. 35 OBJ: 18 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 25. Which of the following represents the correct sequential order for manipulation of pit and

fissure sealants that require etching with phosphoric acid? 1. Cleansing and etching the occlusal surfaces 2. Drying the occlusal surfaces 3. Washing the occlusal surfaces 4. Finishing the occlusal surfaces 5. Polymerizing 6. Applying sealant to the pits and fissures a. 2, 1, 3, 4, 6, 5 b. 1, 2, 4, 3, 5, 6 c. 1, 3, 2, 6, 4, 5 d. 1, 3, 2, 6, 5, 4 e. 3, 1, 2, 6, 4, 5 ANS: D

Feedback The correct order of sequential steps is cleansing and etching the occlusal surfaces, washing the occlusal surfaces, drying the occlusal surfaces, applying sealant to the pits and fissures, polymerizing, and finishing. The correct order of sequential steps is cleansing and etching the occlusal

surfaces, washing the occlusal surfaces, drying the occlusal surfaces, applying sealant to the pits and fissures, polymerizing, and finishing. The correct order of sequential steps is cleansing and etching the occlusal surfaces, washing the occlusal surfaces, drying the occlusal surfaces, applying sealant to the pits and fissures, polymerizing, and finishing. The correct order of sequential steps is cleansing and etching the occlusal surfaces, washing the occlusal surfaces, drying the occlusal surfaces, applying sealant to the pits and fissures, polymerizing, and finishing. The correct order of sequential steps is cleansing and etching the occlusal surfaces, washing the occlusal surfaces, drying the occlusal surfaces, applying sealant to the pits and fissures, polymerizing, and finishing.

DIF: Analysis REF: p. 32 OBJ: 12 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 26. Which composition is used to help prevent caries in the pits and fissures of posterior teeth? a. Glass ionomers b. Polymers c. Acrylic d. Ceramic ANS: B

A B C D

Feedback Glass ionomers are ceTmEeS ntT s.BANKSELLER.COM Pit and fissure sealants are polymers applied to the occlusal surfaces of posterior teeth to prevent pit and fissure caries. Acrylics are used to make complete dentures, portions of removable partial dentures, temporary crowns, custom impression trays, and denture teeth. Ceramics are used in indirect restorations.

DIF: Knowledge REF: p. 28 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) MSC: NBDHE, 5.0 Using preventive agents, 5.2 Pit and fissure sealants, 5.2.1 Mechanisms of action 27. Neutral sodium fluoride is used for patients with composites, ceramics, and glass ionomers,

because it will not a. stain b. etch c. marginate d. remineralize

esthetic restorations.

ANS: B

A B

Feedback Stannous fluoride stains. With neutral sodium fluoride the pH is adjusted to be between 6 and 8. Values of pH in this range should minimize acid etching of restorative materials, such as

C D

composites, compomers, resin-modified glass ionomers, glass ionomers, and ceramics, caused by more acidic APF gels. The gel is neutral and therefore safe for esthetic restorations. Some fluoride varnishes contain ACP remineralization properties.

DIF: Knowledge REF: p. 27 OBJ: 1 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 28. Which of the following terms describes a neutral fluoride gel containing thickening agents? a. Wetting b. Viscous c. Flowable d. Thixotropic ANS: D

A B C D

Feedback Wetting is related to the thickness or thinness of a material and/or surface tension. Viscosity is related to the thickness or thinness of a material and/or surface tension. Flowable is related toTthEeSthi ckAnN esKs S orEtL hiLnE neRss.oCfOaMmaterial and/or surface TB tension. Neutral sodium fluoride foams, gels, and rinses are available. One product is thixotropic and contains sodium fluoride and thickening agents.

DIF: Knowledge REF: p. 28 OBJ: 2 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 29. Which type of fluoride may be responsible for depositing stains on teeth and restorations? a. Acidulated phosphate b. Neutral sodium c. Stannous d. Sodium ANS: C

Feedback A

Acidulated phosphate is used as an alternative to stannous fluoride because it does not stain.

B C D

Neutral sodium is used as an alternative to stannous fluoride because it does not stain. Stannous fluoride products are effective in providing fluoride but can cause staining of tooth surfaces and restorations. Sodium fluoride is used as an alternative to stannous fluoride because it does not stain.

DIF: Knowledge REF: p. 28 OBJ: 3 TOP: CDA, GC, V Patient education and oral healthcare management; C Demonstrate the understanding of plaque control techniques, including but not limited to: Explain the effects of all types of fluoride, the advantages of various methods of administration, and the dangers and results of overdosage MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 30. How should a mouth protector be stored when not in use? a. In a cool, dry place b. In water to prevent shrinkage c. In the case provided by the dentist d. In a denture cleaner to remove any bacteria present ANS: C

A B C D

Feedback While helpful, storing a mouth protector in a cool, dry place is not necessary. A mouth protector should not be stored in water. When the mouth proteTcE toSr T isBdA elN ivKere d,LthLeEaR th.leCteOw SE Mill be given a case to keep it in. Mouth protectors should be rinsed with cool water after use and occasionally cleaned with mild soap and water. Denture cleaners and abrasive dentifrices should not be used.

DIF: Knowledge REF: p. 38 OBJ: 26 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 31. Which light spectrum is used to polymerize sealant materials? a. Incandescent b. Fluorescent c. Ultraviolet d. Visible ANS: D

A B

Feedback Incandescent light sources may affect the surface setting of resin materials. However, the optimum response comes from the visible light spectrum. Fluorescent light sources may affect the surface setting of resin materials. However, the optimum response comes from the visible light spectrum.

C D

Ultraviolet light sources may affect the surface setting of resin materials. However, the optimum response comes from the visible light spectrum. Sealants polymerized by visible light (490 nm wavelength) are one-component systems that require no mixing.

DIF: Knowledge REF: p. 30 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 32. It can be difficult to fill a fissure completely with sealant due to a. air b. debris c. moisture d. all of the above

trapped in the fissure.

ANS: D

A B C D

Feedback All answers are correct. All answers are correct. All answers are correct. Filling the fissure completely is difficult because air frequently is trapped in the bottom of the fissure, or the accumulation of debris and moisture at the base of the fissure prevents itTfrEoS mTbB eiA ngNK seS alE edLL coEmRp. leC teO lyM.

DIF: Knowledge REF: p. 30 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.2.2 Techniques for application 33. Eighty-five percent of dental caries on posterior teeth of children ages 5 to 17 occur on which

surface? a. Mesial b. Distal c. Buccal d. Lingual e. Occlusal ANS: E

A B C D E

Feedback Mesial are smooth surfaces and are not as susceptible to formation of caries. Distal are smooth surfaces and are not as susceptible to formation of caries. Buccal are smooth surfaces and are not as susceptible to formation of caries. Lingual are smooth surfaces and are not as susceptible to formation of caries. The unusual anatomy of the pit and fissure causes such sites to exhibit a high

incidence of dental caries. In fact, 84% of dental caries in children 5 to 17 years of age involve pits. DIF: Knowledge REF: p. 29 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 34. Teeth should be etched with a a. 18%; 15 b. 23%; 30 c. 37%; 60 d. 42%; 45

phosphoric solution for

seconds.

ANS: C

A B C

Feedback Etch material is dispensed at 37% dilution. It takes approximately 60 seconds to obtain an adequate etch. Etch material is dispensed at 37% dilution. It takes approximately 60 seconds to obtain an adequate etch. Etchants are generally 37% solutions of phosphoric acid in water. The solution is left on the tooth for 60 seconds before the surface is washed with a liberal amount of water for at least 15 seconds. Etch material is dispeT nsEeS dT atB3A 7% ioL n.EIR t t. akCeO sM approximately 60 seconds to NKdSiluEtL obtain an adequate etch.

DIF: Knowledge REF: p. 32 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 35. What should the operator do if teeth become contaminated with saliva after they are etched? a. Re-etch, rinse, and dry. b. Rinse the area again and dry it. c. Use the high-velocity suction to dry. d. Add more cotton rolls for moisture control. ANS: A

A B C

Feedback If an etched tooth should become contaminated by saliva, the etching and rinsing steps are repeated. Contamination by saliva will decrease the ability for the sealant to bond. Therefore the tooth should be re-etched, rinsed, and dried prior to placement. Contamination by saliva will decrease the ability for the sealant to bond. Therefore the tooth should be re-etched, rinsed, and dried prior to placement.

Contamination by saliva will decrease the ability for the sealant to bond. Therefore the tooth should be re-etched, rinsed, and dried prior to placement.

DIF: Knowledge REF: p. 32 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.2.2 Techniques for application 36. As the thickness of mouth protector material increases, the energy forces _

transmitted forces a. increase; decrease b. increase; increase c. decrease; increase d. decrease; decrease

, and the

ANS: A

B C D

Feedback As the thickness of a mouth protector material is increased from 2 to 6 mm, the energy absorption is increased, and the transmitted forces on impact are decreased. Thicker materials, however, are more uncomfortable to wear. As the thickness increases, it absorbs blows better and decreases transmitted forces. If the material thickness decreases, blows have an increased impact. As the thickness increases, it absorbs blows better and decreases transmitted forces. If the materialTthEicSkT nB esA sN deKcS reE asLeL s, E blo wC sO haMve an increased impact. R. As the thickness increases, it absorbs blows better and decreases transmitted forces. If the material thickness decreases, blows have an increased impact.

DIF: Comprehension REF: p. 35 OBJ: 18 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 37. Of the following, which would not be a sign of mouth-protector deterioration? a. Tearing b. Bite-through c. Discoloration d. General wear ANS: C

Feedback The breakdown of a mouth protector usually results from one of three causes: bite-through, tearing, or a general deterioration that results from chewing the protector. The breakdown of a mouth protector usually results from one of three causes: bite-through, tearing, or a general deterioration that results from chewing the protector. Mouth-protectors do discolor and stain, but it is not necessarily a sign of

deterioration. The breakdown of a mouth protector usually results from one of three causes: bite-through, tearing, or a general deterioration that results from chewing the protector.

DIF: Knowledge REF: p. 35 OBJ: 21 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents 38. What is the purpose of etching enamel prior to placing a sealant? a. Improve wetting b. Cleaning the enamel surface c. Makes the surface smooth and uniform. d. A and B are correct ANS: D

A B C D

Feedback Etching enamel improves the wetting of the enamel surface. Etching cleans the enamel surface and removes debris that could prevent bonding. Etching the enamel forms spaces for the sealant material to penetrate and form retentive tags. A and B are correct answers.

0 BANKS OE BL J:LE 8 R.COM DIF: Knowledge REF: TpE . S3T TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants. MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.2.2 Techniques for application 39. How many seconds should the light-activated sealant material be polymerized with the curing

wand? a. 10 b. 15 c. 20 d. 25 ANS: C

A B C D

Feedback 10 seconds is inadequate for a complete cure of the material. 15 seconds is inadequate for a complete cure of the material. The visible light wand should remain activated for 20 seconds in order to provide an adequate cure of the material. Over-curing of the material is not necessary.

DIF: Knowledge REF: p. 30 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2.

Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.2.2 Techniques for application 40. What is the optimum mixing time for a two-step, self-curing, sealant material? a. 5 to 10 seconds b. 10 to 15 seconds c. 15 to 20 seconds d. 20 to 25 seconds ANS: C

A B C D

Feedback Mixing the two components for 10 to 15 seconds will not insure a homogeneous mixture. The optimum mixing time for a two-step sealant material is 10 to 15 seconds. Mixing a two-step sealant for more than 15 seconds will reduce the operator’s working time. Mixing a two-step sealant for more than 15 seconds will reduce the operator’s working time.

DIF: Knowledge REF: p. 30 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action SHORT ANSWER 1. Identify four criteria for not using a pit and fissure sealant. ANS:

Current evidence indicates that sealants should not be used on the teeth of a patient who does not cooperate in maintaining good oral hygiene, on occlusal surfaces where pits and fissures do not exist, on teeth that have been free of caries for several years, and on teeth with many proximal lesions. DIF: Application REF: p. 32 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.1.1 Mechanisms of action 2. Discuss the significance of placing a pit and fissure sealant over existing caries. ANS:

One concern is what happens to dental caries that are purposely or inadvertently left beneath sealed pits and fissures. Several studies have reported that the number of cultivable microorganisms from carious dentin left in situ in sealed pits and fissures for up to 5 years was considerably less than before sealant was applied. Sealing a suspected carious pit and fissure appears to be a reasonable clinical service if appropriate clinical observation is maintained. DIF: Comprehension REF: p. 32 OBJ: 12 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) 2. Describe how to prepare, mix, deliver, and store other dental materials, including but not limited to e. pit and fissure sealants MSC: NBDHE, 5.0 Using preventive agents, 5.1 Fluoride: systemic and topical, 5.2.2 Techniques for application 3. List the steps for cleaning a mouth protector after each use. ANS:

After each use, the following steps should be performed: 1. Rinse your mouth protector under cold tap water. 2. Occasionally clean your mouth protector in a solution of soap and cool water. 3. Do not scrub your mouth protector with an abrasive dentifrice. 4. Do not use alcohol solutions or denture cleansers to clean your mouth protector. 5. Store your mouth protector in the container provided. DIF: Knowledge REF: p. 38 OBJ: 26 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: TNE BS DT HB E,A5N .0KUSsiE ngLpLrE evR en.tiC veOaMgents, 5.3 Other preventive agents 4.

Compare and contrast the three types of mouth protectors available for athletes to use. ANS:

There are three types of mouth protectors available to the student athlete. They are stock, self-bite, and custom made. Stock trays can be purchased in the sporting goods section of most stores and are disliked by athletes because it is difficult to talk, and the stock mouth protector does not fit well. Self-bite, also known as boil and bite, fit marginally better, but athletes often complain of gagging and a foul taste. Custom-made mouth protectors provide the athlete with optimum coverage and ease of speech. They are also tasteless. DIF: Analysis REF: p. 33 OBJ: 17 TOP: CDA, GC, IV Laboratory materials and procedures, B Demonstrate an understanding of laboratory procedures, including but not limited to 2. fabricate custom occlusal appliances and bleaching trays MSC: NBDHE, 5.0 Using preventive agents, 5.3 Other preventive agents

Chapter 04: Direct Esthetic Restorative Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Which of the following is the most popular direct esthetic dental restorative material? a. Composite b. Compomer c. Glass ionomer d. Hybrid ionomer ANS: A

A B

Feedback Composite is the most popular direct esthetic restorative material. Compomers have distinct advantages as direct esthetic restorations. However, they are weaker than composite resins and should be used under specific parameters. Glass ionomers have distinct advantages as direct esthetic restorations. However, they are weaker than composite resins and should be used under specific parameters. Hybrid ionomers have distinct advantages as direct esthetic restorations. However, they are weaker than composite resins and should be used under specific parameters.

DIF: Knowledge REF: TpE . S4T 2 BANKS OE BL J: LE 1 R.COM TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Which of the following direct esthetic restorative materials releases the least fluoride? a. Hybrid ionomer b. Glass ionomer c. Compomer d. Composite ANS: D

A B C D

Feedback Hybrid ionomer contains a fluoride ion that leaches into the tooth structure for added protection. Glass ionomer contains a fluoride ion that leaches into the tooth structure for added protection. Compomer contains a fluoride ion that leaches into the tooth structure for added protection. Composite releases the least fluoride.

DIF: Knowledge REF: p. 42 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1,

Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. Which of the following is not a direct esthetic restorative material? a. Ceramic b. Composite c. Compomer d. Glass ionomer ANS: A

B C D

Feedback Currently, four types of materials are being used as direct esthetic dental restorations: composites, compomers, resin-modified glass ionomers, and glass ionomers. Ceramic restorations are indirect; fabricated outside of the mouth. Composite is used in direct placement esthetic restorations. Ceramic is used for indirect esthetic restorations. Compomer is used in direct placement esthetic restorations. Ceramic is used for indirect esthetic restorations. Glass ionomer is used in direct placement esthetic restorations. Ceramic is used for indirect esthetic restorations.

DIF: Knowledge REF: p. 42 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

TESTBANKSELLER.COM

4. Which of the following statements is true of silane in composite materials? a. Silane forms the dispersed inorganic filler particles. b. Silane forms the dispersed organic filler particles. c. Silane is a coupling agent on the filler particles. d. Silane forms the resin matrix. ANS: C

A B C D

Feedback Silane is a coupling agent that allows bonding of particles. It does not form them. Silane is a coupling agent that allows bonding of particles. It does not form them. Silane is a coupling agent on the filler particles. Its purpose is to produce a good bond between the matrix and the filler. Silane is a coupling agent that allows bonding of particles. It does not form them.

DIF: Knowledge REF: p. 44 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. Which type of composite has the smallest filler particle size?

a. b. c. d. e.

Microhybrid Microfilled Nanofilled Packable Flowable

ANS: C

A B C D E

Feedback Microhybrid has particle sizes measured in microns. Nanofilled particles are measured in smaller nanometers. Microfilled has particle sizes measured in microns. Nanofilled particles are measured in smaller nanometers. Nanofilled composites have the smallest particle size. Packable has particle sizes measured in microns. Nanofilled particles are measured in smaller nanometers. Flowable has particle sizes measured in microns. Nanofilled particles are measured in smaller nanometers.

DIF: Knowledge REF: p. 43 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. Which type of setting reaction is utilized by a composite restorative material? a. Gelation b. Reduction c. Hysteresis d. Polymerization ANS: B

A B C D

Feedback Gelation has reactions not associated with direct esthetic restorations. The setting reaction of a composite restorative material is polymerization. Hysteresis has reactions not associated with direct esthetic restorations. Reduction has reactions not associated with direct esthetic restorations.

DIF: Knowledge REF: p. 45 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. In a visible, light-curing, direct composite system, which component is the light absorbed by? a. Diketone, which starts the polymerization reaction in the presence of an organic

peroxide initiator b. Diketone, which starts the polymerization reaction in the presence of an organic

amine c. Organic peroxide initiator and organic amine accelerator d. Organic peroxide initiator alone

ANS: B

C D

Feedback In a visible, light-curing, direct composite system, the light is absorbed by a diketone, which starts the polymerization reaction in the presence of an organic amine. In a visible, light-curing, direct composite system, the light is absorbed by a diketone, which starts the polymerization reaction in the presence of an organic amine. Organic peroxide initiator activates the two-paste, self-cure systems. Organic peroxide initiator activates the two-paste, self-cure systems.

DIF: Knowledge REF: p. 45 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. Which of the following statements is true of polymerization shrinkage of composite

restorative materials? a. Microfilled composites shrink less than microhybrid composites, because microhybrid composites have less resin. b. Stresses from polymerization shrinkage cannot exceed the bond strength of a composite to tooth structure. c. Incremental addition and polymerization of composite in layers will reduce the effective shrinkage. d. Bulk addition of composite will reduce the effective shrinkage. ANS: D

A B C D

Feedback Microhybrid composites shrink less during setting than microfilled types, because the microhybrid composites have less resin. Stresses from polymerization shrinkage can exceed the bond strength of a composite to tooth structure, resulting in marginal leakage. Incremental addition and polymerization of composite in layers will reduce the effective shrinkage. Bulk addition will increase the effective shrinkage.

polymer has a a. higher; higher b. higher; lower c. lower; higher d. lower; lower

the linear coefficient of thermal expansion, because the _ value than the filler.

ANS: A

A B

Feedback The more resin matrix, the higher the linear coefficient of thermal expansion, because the polymer has a higher value than the filler. Microfilled composites have higher values for thermal expansion than microhybrid composites. Therefore the more resin matrix a material has, the higher the linear coefficient of thermal expansion. The lower the matrix, the lower the value. Microfilled composites have higher values for thermal expansion than microhybrid composites. Therefore the more resin matrix a material has, the higher the linear coefficient of thermal expansion. The lower the matrix, the lower the value. Microfilled composites have higher values for thermal expansion than microhybrid composites. Therefore the more resin matrix a material has, the higher the linear coefficient of thermal expansion. The lower the matrix, the lower the value.

DIF: Analysis REF: p. 46 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. Which of the following statements is correct when contrasting microhybrid composites with

microfilled composites? a. Microhybrid composites have higher water sorption. b. Microfilled compositesThEaS veThBigAhNerKcSoE mL prLeE ssR iv. eC stO reMngth. c. Microhybrid composites have more polymerization shrinkage. d. Microhybrid composites have a lower elastic modulus in compression. e. Microfilled composites have a higher linear coefficient of thermal expansion. ANS: D

A B C D E

Feedback Microhybrid composites have lower water sorption. Microfilled composites have a higher linear coefficient of thermal expansion. Microhybrid composites have less polymerization shrinkage. Microhybrid composites have a higher elastic modulus in compression than microfilled composites. Microfilled composites have a lower compressive strength than microhybrid composites.

DIF: Comprehension REF: p. 43 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. A bond strength of

MPa is an estimated requirement to prevent marginal gaps as a result of polymerization shrinkage during placement of composite restorations. a. 0.01

b. 1 c. 10 d. 20 ANS: D

A B C D

Feedback 0.01 is well below the estimated MPa requirement and would exacerbate the potential for marginal gaps. 1 is well below the estimated MPa requirement and would exacerbate the potential for marginal gaps. 10 is well below the estimated MPa requirement and would exacerbate the potential for marginal gaps. A bond strength of 20 MPa is an estimated requirement to prevent marginal gaps as a result of polymerization shrinkage during placement of composite restorations.

DIF: Knowledge REF: p. 45 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. Sensitivity associated with placement of composite restorations has been reported in about

% of cases. a. b. c. d. e.

1 10 25 50 75

ANS: B

A B C D E

Feedback Sensitivity associated with placement of composite restorations has been reported in about 10% of cases. Sensitivity associated with placement of composite restorations has been reported in about 10% of cases. Sensitivity associated with placement of composite restorations has been reported in about 10% of cases. Sensitivity associated with placement of composite restorations has been reported in about 10% of cases. Sensitivity associated with placement of composite restorations has been reported in about 10% of cases.

DIF: Knowledge REF: p. 47 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

13. Currently acceptable composites for posterior applications require clinical studies

demonstrating a loss of surface contour less than a. 5 b. 50 c. 100 d. 250 e. 5000

µm over a 5-year period.

ANS: D

Feedback Currently acceptable composites for posterior applications require clinical studies demonstrating a loss of surface contour less than 250 µm over a 5-year period, or an average of 50 µm per year of clinical service. Currently acceptable composites for posterior applications require clinical studies demonstrating a loss of surface contour less than 250 µm over a 5-year period, or an average of 50 µm per year of clinical service. Currently acceptable composites for posterior applications require clinical studies demonstrating a loss of surface contour less than 250 µm over a 5-year period, or an average of 50 µm per year of clinical service. Currently acceptable composites for posterior applications require clinical studies demonstrating a loss of surface contour less than 250 µm over a 5-year period, or an average of 50 µm per year of clinical service. Currently acceptable composites for posterior applications require clinical studies demonstrating a loss of surface contour less than 250 µm over a 5-year period, or an average of 50 µm per year of clinical service.

restorations? a. Induced internal stress b. An occlusal interference c. Microleakage of bacteria d. The use of acid etchant during placement e. Both B and D ANS: E

A B C D E

Feedback B and D are correct. Effective finishing and polishing of the restoration at the time of placement will eliminate high occlusion. B and D are correct. Use of a low-strength liner prior to etching will protect the pulp. The most likely causes of sensitivity following placement of composite restorations are induced internal stress and microleakage of bacteria.

DIF: Comprehension REF: p. 47 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites and g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. With

-generation bond agents, etching and priming are accomplished at the same time, and rinsing is not required. a. third b. fourth c. fifth d. sixth ANS: D

A B C D

Feedback Third-generation bond agents are all associated with multiple steps. Fourth-generation bond agents are all associated with multiple steps. Fifth-generation bond agents are all associated with multiple steps. With sixth- and seventh-generation bonding agents, etching and priming are accomplished at the same time, and rinsing is not required.

DIF: Knowledge REF: p. 47 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners TgESSuT MSC: NMDHE, 6.0 Providin ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General 16. Which of the following statements is true of single- and two-paste composites? a. Single-paste composites are light activated. b. Single-paste composites may be dual cured. c. Compules are a component of two-paste composites. d. An automix syringe is a component of single-paste composites. ANS: A

A B C D

Feedback Single-paste composites are light activated. Some forms of two-paste composites are dual cured. Compules are a component of single-paste composites. An automix syringe is a component of two-paste composites.

DIF: Knowledge REF: p. 47 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. What is/are (an) advantage(s) of placing composite into the plastic tip of a syringe and

injecting it into the cavity preparation? a. Allows the use of large mixes

b. c. d. e.

Facilitates placement of the material in the areas of retention Reduces incorporation of voids into the composite during insertion A, B, and C are correct. Only B and C are correct.

ANS: E

A B C D

Feedback Using a syringe for placement of composite resin allows the operator to place smaller increments of material. B and C are correct. B and C are correct. Advantages of placing composite into the plastic tip of a syringe and injecting it into the cavity preparation include that the syringe allows the use of small mixes, reduces incorporation of voids into the composite during insertion, and facilitates placement of the material in the areas of retention. B and C are correct.

DIF: Comprehension REF: p. 47 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. Which of the following statements is correct about flowable composite resins? a. Are recommended for low-stress-bearing restorations b. Have a high modulus of elasticity c. Have a low modulus ofTeElaSstTicBitA y NKSELLER.COM d. A and B e. A and C ANS: E

A B C D E

Feedback Flowable composites are recommended for low-stress-bearing restorations. They have a low modulus of elasticity, which is the ratio of stress to strain. Flowable composites are recommended for low-stress-bearing restorations. They have a low modulus of elasticity, which is the ratio of stress to strain. Flexible materials have a low modulus of elasticity, and stiff materials have a high modulus of elasticity. Flowable composites are recommended for low-stress-bearing restorations. They have a low modulus of elasticity, which is the ratio of stress to strain. Flowable composites are recommended for low-stress-bearing restorations. They have a low modulus of elasticity, which is the ratio of stress to strain.

DIF: Comprehension REF: p. 48 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

19. Which of the following statements is true of flowable composites when contrasted with

microhybrid composites? a. They have lower viscosity than microhybrid composites. b. They have a higher filler content than microhybrid composites. c. They have higher wear resistance than microhybrid composites. d. They exhibit lower polymerization shrinkage than microhybrid composites. ANS: D

A B C D

Feedback Flowable composites have lower viscosity than microhybrid composites. Flowable composites have a lower filler content than microhybrid composites. Flowable composites have lower wear resistance than microhybrid composites. This makes them more flexible and well suited for fabrication areas, but they do exhibit more polymerization shrinkage.

DIF: Knowledge REF: p. 48 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Which type of direct composite has a wear rate most similar to dental amalgam? a. Packable composite b. Flowable composite c. Microfilled composite d. Microhybrid composite ANS: A

A B C D

Feedback Packable has a low wear rate (3.5 µm/year), similar to that of amalgam. Flowable has higher wear rates than are recommended for stress-bearing areas. Microfilled has higher wear rates than are recommended for stress-bearing areas. Microhybrid has higher wear rates than are recommended for stress-bearing areas.

DIF: Knowledge REF: p. 49 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Which of the following statements is true when contrasting composite core material with

amalgam? a. Composite can be finished immediately and prepared for a crown at the same appointment, whereas amalgam cannot be prepared for a crown at the same appointment. b. Composite materials have good color under ceramic, but amalgam does not. c. Composite materials are more difficult to contour than amalgam materials. d. A, B, and C are correct. e. A and B are correct.

ANS: E

A B C D E

Feedback Only A and B are correct. Only A and B are correct. Composite resin materials are easier to contour than amalgam because of the increased working time and the ability to not overfill. Only A and B are correct. Amalgam cannot be prepared for a crown at the same time as the placement appointment because of delayed setting expansion or contraction. Composite materials have better color under ceramic while the silver-gray color of amalgam can bleed through. Composite materials are easier to contour than amalgam materials.

DIF: Comprehension REF: p. 51 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Advantages of composite provisional materials over acrylic provisional materials include a. lower cost. b. harder, more brittle texture. c. doughy stage for easier handling. d. lower heat release during curing. ANS: D

A B C D

Feedback They are more expensive. They are harder and more brittle, which are listed in Table 4-5 as disadvantages of composite. Acrylic is listed as having a doughy stage for easier handling than composite. Composite provisional materials release less heat during curing than acrylic provisional materials.

DIF: Knowledge REF: p. 51 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to f. Temporary restorative materials MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. When composites are repaired, the repair bond strength is about

strength of the original composite. a. 100 to 120 b. 80 to 100 c. 60 to 80 d. 40 to 60 e. 20 ANS: C

% of the cohesive

A B C D E

Feedback Option A is higher than the given percent rate. Option B is higher than the given percent rate. The repair bond strength is about 60 to 80% of the cohesive strength of the original composite. Option D is lower than the given percent rate. Option E is lower than the given percent rate.

DIF: Knowledge REF: p. 51 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. Which of the following do compomers contain? a. Dimethacrylate (Bis-GMA) b. Urethane dimethacrylate (UDMA) oligomers c. Monomers modified by polyacid groups with fluoride-releasing silicate glasses. d. A powder of aluminosilicate glass and a water solution of polymers and

copolymers of acrylic acid. ANS: C

A B C D

Feedback Bis-GMA is associated with composite resins, microfilled, and microhybrids. UDMA is associated with composite resins, microfilled, and microhybrids. Compomers contain m erA sN mK odSiE fieLdLbEyRp. olC yaOcM id groups with ToEnSom TB fluoride-releasing silicate glasses. Option D is associated with glass ionomer.

DIF: Knowledge REF: p. 52 OBJ: 10 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. It is recommended that glass ionomer restorations be used in Class

restorations where

esthetics is not critical. a. I b. II c. III d. IV e. V ANS: E

A B

Feedback Class Is are load-bearing areas, and glass ionomers are not strong enough to withstand biting forces. Class IIs are load-bearing areas, and glass ionomers are not strong enough to withstand biting forces.

C D E

Class IIIs are highly visible areas in which esthetics is an issue. Class IVs are highly visible areas in which esthetics is an issue. It is recommended that glass ionomer restorations be used in Class V restorations where esthetics is not critical. They are recommended for patients with high risk of caries.

DIF: Knowledge REF: p. 52 OBJ: 13 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to e. glass ionomers MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. What are the components of the smear layer? a. Hydroxyapatite and partially denatured collagen b. Calcium hydroxide c. Adhesive d. Etchant e. Primer ANS: A

A B C D E

Feedback The smear layer consists of hydroxyapatite and partially denatured collagen. Calcium hydroxide is used as a low-strength liner and will stimulate the formation of reparative dentin. Adhesive is related to the bonding process. Etchant removes the smear layer and prepares enamel and dentin to receive the esthetic restoration. Primer is related to the bonding process.

DIF: Knowledge REF: p. 54 OBJ: 23 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. Which of the following statements is true regarding composite curing times? a. Darker shades require shorter curing times than lighter shades. b. Curing times with PAC lights are longer than for QTH or LED lights. c. Microhybrid composites require longer curing times than microfilled composites. d. More opaque composites require longer curing times than more translucent

composites. ANS: D

A B C D

Feedback Shade should not affect curing time. QTH or LED lights are more intense than PAC lights. Microfilled composites take longer to cure than microhybrid composites. More opaque composites require longer curing times than more translucent composites.

DIF: Knowledge REF: p. 55 OBJ: 27 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. Glass ionomers are typically reserved for which type of restoration? a. Posterior interproximal lesions b. Anterior interproximal lesions c. Cervically eroded areas d. Pit and fissure lesions ANS: C

A B C D

Feedback Posterior interproximal lesions require a restorative material with more strength and wear resistance. Anterior interproximal lesions require a restorative material with more strength and wear resistance. Areas of cervical erosion benefit from using glass ionomer. Pit and fissure lesions require a restorative material with more strength and wear resistance.

ToEt S LpLoE 29. Which of the following is n trT ueBaAbN ouKt S coEm siR te.reCsO inMmaterials? a. High strength b. Esthetically pleasing c. High wear resistance d. High fluoride content ANS: D

A B C D

Feedback Composite resins are esthetically pleasing, strong, and have high wear resistance. Composite resins are esthetically pleasing, strong, and have high wear resistance. Composite resins are esthetically pleasing, strong, and have high wear resistance. Composite resins have little to no fluoride content.

DIF: Knowledge REF: p. 42 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 30. What does the composition of composite resin material consist of? a. Resin matrix

b. c. d. e.

Organic filler particles Inorganic filler particles A and B are correct. A and C are correct.

ANS: E

D E

Feedback Composites consist of three phases: resin matrix, dispersed inorganic filler particles, and silane coupling agent on the filler particles to produce a good bond between the matrix and the filler. Filler particles in composite resin materials include quartz, lithium aluminum silicate, and barium, strontium, zinc, or ytterbium glasses. All are inorganic materials. Filler particles in composite resin materials include quartz, lithium aluminum silicate, and barium, strontium, zinc, or ytterbium glasses. All are inorganic materials. A and C are correct. A and B are correct.

DIF: Knowledge REF: p. 44 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 31. Which of the following organic fillers are radiopaque? a. Lithium aluminum silicTaE b. Crystalline silica c. Strontium d. A, B, and C are all correct. ANS: C

A B C D

Feedback Lithium aluminum silicate fillers are radiolucent. Crystalline silica fillers are radiolucent. Fine fillers that contain barium, strontium, zinc, or ytterbium atoms are radiopaque with the radiopacity proportional to the volume fraction of the filler. Option C is the only correct answer.

DIF: Knowledge REF: p. 43 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. Which of the following organic fillers are radiolucent? a. Lithium aluminum silicate b. Crystalline silica c. Strontium d. A and B are correct.

e. B and C are correct. ANS: D

A B C D E

Feedback Quartz (crystalline silica) and lithium aluminum silicate are both radiolucent. A and B are correct. Strontium is radiopaque. Quartz (crystalline silica) and lithium aluminum silicate are both radiolucent. A and B are correct.

DIF: Knowledge REF: p. 44 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 33. What component initiates the polymerization reaction of a self-cure composite resin? a. Diketone in the presence of an organic amine b. Visible curing light system c. Organic peroxide initiator d. Dimethacrylate ANS: C

A B C D

Feedback In self-curing systems, polymerization is accomplished with an organic peroxide initiator and an organic amine accelerator. EpLoLsiEteRs.ysCteOmMthat uses visible light to Curing lights relate toTaEoSnT e-B paAsN teKcS om cure. In self-curing systems, polymerization is accomplished with an organic peroxide initiator and an organic amine accelerator. Dimethacrylate is a resin matrix.

DIF: Knowledge REF: p. 45 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. What occurs if bond strength is exceeded and gaps occur at the cavosurface margin? a. Inadequate cure b. Inadequate etch c. Saliva contamination d. Polymerization shrinkage ANS: D

A B C D

Feedback Inadequate cure affects adhesion rather than strength. Inadequate etch affects adhesion rather than strength. Saliva contamination affects adhesion rather than strength. Even with acid etching of enamel and dentin and use of bonding agents, stresses

from polymerization shrinkage can exceed the bond strength of a composite to tooth structure, and, as a result, marginal leakage can occur. DIF: Knowledge REF: p. 46 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 35. Which of the following have the highest rates of thermal expansion? a. Nanofilled composites b. Microfilled composites c. Macrofilled composites d. Microhybrid composites ANS: B

A B C D

Feedback Nanofilled composites have lower values of thermal expansion. Microfilled composites have higher values for thermal expansion than microhybrid composites. Macrofilled composites have lower values of thermal expansion. Microhybrid composites have lower values of thermal expansion.

DIF: Knowledge REF: p. 46 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: TNE MSDTHBEA , 6N.0KPSroEvL idL inE gR S. upC poOrM tive Treatment Services, 6.5 General 36. Why would a dentin bonding agent not be used when placing a resin-modified glass ionomer? a. It decreases the release of fluoride b. Using a curing light is not necessary. c. The material does not bond to tooth structure. d. The material is used for temporary restorations. ANS: A

A B C D

Feedback Resin-modified glass ionomers are recommended for patients with a high caries rate. The use of dentinal bonding agents decreases the release of fluoride. Resin-modified glass ionomers can either be light cured or self-cured. Resin-modified glass ionomers bond to tooth structure. Resin-modified glass ionomers are used as a permanent restoration because they release the fluoride ion and they are more esthetically pleasing than glass ionomer cements.

DIF: Knowledge REF: p. 53 OBJ: 17 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to d. dentin bonding materials MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

37. Why are composite materials for anterior restorations used over other restorative materials? a. Minimal surface erosion b. Resistance to biting forces c. Low rate of recurrent caries d. Minimal degradation in the oral environment ANS: C

A B C

Feedback The problem with composites is the loss of surface contour of composite restorations in the mouth. Anterior restorations suffer abrasive wear from chewing and toothbrushing. Clinical studies have shown that composites are superior materials for anterior restorations in which esthetics is essential and occlusal forces are low. Color changes are minimal; marginal adaptation is good; and recurrent decay is low. Anterior restorations suffer from erosive wear from degradation of the composite in the oral environment.

DIF: Knowledge REF: p. 46 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. How can postoperative sensitivity be avoided? a. Placing larger layers of material b. Using a high-strength base c. Using a low-strength liT neEr d. All of the above are correct. e. Only B and C are correct. ANS: D

A B C D E

Feedback Postoperative sensitivity can be reduced by placing and curing the layers in small increments to limit the amount of polymerization shrinkage. B and C are correct answers. B and C are correct answers. Incremental placement of the composite, excellent isolation during placement, and use of bases to protect the pulp are recommended solutions. B and C are correct answers.

DIF: Comprehension REF: p. 47 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39. In the event that an esthetic material is required for a direct, posterior, load-bearing

restoration, a. core

composite is the material of choice.

b. flowable c. packable d. laboratory ANS: C

A B C D

Feedback Core composites are used to replace tooth structure prior to the placement of a crown. Flowable composites are not strong enough to place in load-bearing areas. These composites (see Table 4-2) are recommended for use in Class I, II, and VI (MOD) cavity preparations. Laboratory composites are used for indirect restorations.

DIF: Knowledge REF: p. 49 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. Compomers are recommended for patients with a. low caries b. medium caries c. high caries d. any level of

risk.

ANS: B

A B C D

Feedback Low caries risk would not need a material containing a fluoride ion. Compomers are recommended for patients with medium caries risk. High caries risk might require a material with a higher level of fluoride release. Not all patients are candidates for compomer restorative materials.

DIF: Knowledge REF: p. 51 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Why is it important to finish and polish a composite restoration after it is placed? a. Reduces staining b. Prevents percolation c. Eliminates microleakage d. Maintains good oral hygiene ANS: D

A B C

Feedback Stain is associated with the amount of exposed matrix in the composite material. Thermal expansion is very close to that of tooth structure. The material expands and contracts at a similar rate as the tooth. Microleakage occurs when a margin is exposed. If the restoration has been

adequately finished at the time of placement, microleakage should not be a factor. A smooth surface helps prevent the retention of plaque.

DIF: Knowledge REF: p. 48 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 42. Which of the following esthetic restorative materials is best suited for Class I posterior

restorations? a. Microfilled b. Microhybrid c. Glass ionomer d. Bulk composite ANS: D

A B C D

Feedback Microfilled materials are better suited for anterior esthetic restorations in low-stress-bearing areas. Microhybrid materials are better suited for anterior esthetic restorations in low-stress-bearing areas. Glass ionomer cements are best utilized along the gum line, in class V restorations, and for patients with high caries rates. Bulk resin materials have larger filler particles that allow it to hold up under the stresses of chewing.

DIF: Knowledge REF: p. 49 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast microfilled and microhybrid composite resin materials. ANS:

Microhybrid materials contain blends of fine and microfine filler particles with as much as 84% filler by weight. The microfine filler particles fit in spaces between the fine filler particles, producing a total filler concentration of 70% by volume, which results in improved properties. Microfilled composites contain microfine fillers with high surface areas. Only 35% to 50% by volume of these particles can be used with the resin matrix and still produce a paste of acceptable viscosity. DIF: Analysis REF: p. 43 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of

Materials 2. Explain the process of polymerization shrinkage of composite resin materials and why it is

significant in the life of a restoration. ANS:

Microhybrid composites shrink less during setting than microfilled types because the microhybrid composites have less resin. Even with acid etching of enamel and dentin and use of bonding agents, stresses from polymerization shrinkage can exceed the bond strength of a composite to tooth structure, and, as a result, marginal leakage can occur. DIF: Comprehension REF: p. 45 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials 3. Compare and contrast direct placement resins to laboratory resins. ANS:

Composite resin materials have a shorter life span than indirect or laboratory resins. Direct placement resins stain easily and wear over a relatively short period of time when compared to laboratory resins. Crowns, inlays, veneers bonded to metal substructures, and metal-free bridges are prepared indirectly on dies from composites processed in the laboratory (see Table 4-2) using various combinations of light, heat, pressure, and vacuum, which increase the polymerization and the wear resistance. DIF: Application REF: p. 51 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NBDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and Manipulation of Materials

Chapter 05: Dental Amalgam Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Which component of dental amalgam exists as a liquid in the capsule before trituration? a. Tin b. Silver c. Copper d. Mercury ANS: D

A B C D

Feedback Tin metals are solid powders. Silver metals are solid powders. Copper metals are solid powders. Mercury is the sole liquid in the capsule.

DIF: Knowledge REF: p. 59 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

TESTBANKSELLER.COM

2. A freshly mixed mass of amalgam has a puttylike consistency for a. 1 to 2 b. 4 to 5 c. 9 to 10 d. 15

minutes.

ANS: A

B C D

Feedback A freshly mixed mass of amalgam has a puttylike consistency for 1 to 2 minutes. The amalgam must be manipulated into the cavity preparation during this time. The amalgam progresses to a carvable consistency for an additional 2 to 4 minutes. This time is beyond the reaction limits, and carving after that point could result in fracture. This time is beyond the reaction limits, and carving after that point could result in fracture. This time is beyond the reaction limits, and carving after that point could result in fracture.

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 3. Which of the following is not an advantage of dental amalgam when contrasted with direct

resin composite? a. Longevity b. Superior esthetics c. Marginal integrity in subgingival areas d. Ease of placement in diverse clinical situations ANS: B

A B

C D

Feedback Longevity decreases when using an esthetic material. Alternate restorative materials such as direct composite suffer from clinical problems such as expense, shorter longevity, and technique sensitivity. However, amalgams are not considered esthetic materials. Marginal integrity decreases when using an esthetic material. Ease of placement decreases when using an esthetic material.

DIF: Knowledge REF: p. 58 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

EoSuT StE%LL 4. High-copper amalgam hasTab t BANKw coEpR pe.rC . OM a. 3 b. 5 to 10 c. 13 to 30 d. 30 to 40 e. 40 to 50 ANS: C

A B C D E

Feedback Low-copper amalgams have a copper content less than 13 wt % and are rarely used today. Low-copper amalgams have a copper content less than 13 wt % and are rarely used today. High-copper amalgam has about 13 to 30 wt % copper. This percentage is far beyond the set parameters for copper content in amalgam. This percentage is far beyond the set parameters for copper content in amalgam.

5. High-copper amalgams have a. more corrosion b. higher strength c. better longevity d. A and C are correct. e. B and C are correct.

_ than low-copper amalgams.

ANS: E

A B C D E

Feedback High-copper amalgams have higher strength, less corrosion, and better longevity than low-copper amalgams. B and C are correct. B and C are correct. High-copper amalgams have higher strength, less corrosion, and better longevity than low-copper amalgams. B and C are correct.

DIF: Comprehension REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 6. Which component of earlier low-copper amalgam caused a significant, unacceptable

expansion of amalgam when it was contaminated with moisture during placement? a. Mercury b. Copper c. Silver d. Zinc e. Tin ANS: E

A B C D

Feedback Mercury elements are used in today’s dental amalgam. Copper elements are used in today’s dental amalgam. Silver elements are used in today’s dental amalgam. Zinc causes a significant, long-term, and clinically unacceptable expansion of the amalgam when it is contaminated with moisture during placement. Such immediate expansion may fracture teeth. Tin elements are used in today’s dental amalgam.

7. An admixed dental amalgam contains a. only irregularly b. only spherically c. neither irregularly shaped nor spherically d. a mixture of irregularly shaped and spherically

shaped alloy powder particles.

ANS: D

A B C D

Feedback Irregularly shaped alloy particles are used in conjunction with spherical particles. Spherically shaped particles require more mercury and will set faster. Irregularly shaped alloy particles are used in conjunction with spherical particles. An admixed dental amalgam alloy contains a mixture of irregularly shaped and spherical silver alloy powder particles.

DIF: Knowledge REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 8. Which of the following statements is true of admixed amalgam in contrast with spherical

amalgam? Admixed amalgams a. contain only irregularly shaped particles, not spherically shaped particles. b. require more condensation force than spherical amalgams. c. require less mercury than spherical amalgams. d. set somewhat faster than spherical amalgams. ANS: B

A B C D

Feedback Admixed amalgams are a combination of irregular and spherical particles. Admixed amalgams require more condensation force than spherical amalgams. This property is considered an advantage to obtain good proximal contacts. Admixed amalgams require more mercury. Spherical amalgams set somewhat faster than admixed amalgams.

DIF: Analysis REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 9. Which of the following elements is a liquid at room temperature? a. Beryllium b. Mercury

c. Gallium d. Sodium e. Lead ANS: B

A B C D E

Feedback Beryllium is a solid. Mercury is the only metallic element in the periodic table that is a liquid at room temperature. Gallium melts at slightly above room temperature. Sodium is a solid. Lead is a solid.

amount of mercury? a. Mercury added to alloy particles and mixed with a mortar and pestle b. Silver alloy powder and mercury sealed into a disposable hard plastic capsule c. Powder compressed into tablets and mixed with mercury in a reusable mixing capsule d. None of the above ANS: B

A B C D

Feedback A premeasured capsule is the recommended method of dispensing amalgam. The precapsulated method provides the proper ratio of alloy powder to mercury, limits exposure to mercury of the dental staff, and keeps the mercury clean. A premeasured capsule is the recommended method of dispensing amalgam. A premeasured capsule is the recommended method of dispensing amalgam.

longevity in today’s high-copper amalgam restorations? a. Silver–tin b. Copper–tin c. Mercury–tin d. Silver–copper

ANS: B

A B C D

Feedback Silver–tin is not a component of the gamma-2 phase. Elimination the mercury–tin compound during the gamma-2 phase increases the clinical longevity in today’s high-copper amalgam restorations. Copper–tin is not a component of the gamma-2 phase. Silver–copper is not a component of the gamma-2 phase.

DIF: Comprehension REF: p. 61 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 12. In the set mass of amalgam, original silver alloy particles comprise over

% of the

volume. a. 10 b. 25 c. 50 d. 75 e. 90 ANS: C

A B C

D E

Feedback Ten is too low to be useful. Twenty-five is too low to be useful. In the set mass of amalgam, original silver alloy particles comprise over 50% of the volume of the material. The set volume is significant to the strength and corrosion resistance of the product. Seventy-five is too high. Ninety is too high.

DIF: Knowledge REF: p. 59 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

mercury vapor is released from dental amalgam per day, as a result of chewing.

13.

a. 1 to 2 µg b. 2 to 4 wt % c. 50% d. No ANS: A

A B C D

Feedback In practice, minute amounts of mercury vapor (approximately 1 to 2 µg per day) are released as a result of chewing. This is the weight of copper content. This is the weight of silver by volume. Small amounts of mercury vapor are released while chewing.

DIF: Knowledge REF: p. 60 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 14. Which phase is absent in a high-copper amalgam? a.  b.  c.  d.  ANS: D

A B C D

Feedback This phase remains in a high-copper amalgam setting. This phase remains in a high-copper amalgam setting. This phase remains in a high-copper amalgam setting. Gamma-2 () is absenTtEinSaThBigAhN-cKoS ppEeLr L am EaRlg.aCmO. M

DIF: Knowledge REF: p. 65 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 15. In its reacted state, little mercury is released from an amalgam. Little free mercury is available

to be released from a set amalgam. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Both statements are correct. Both statements are correct. Both statements are correct. Both statements are correct.

DIF: Comprehension

REF: p. 60

OBJ: 8

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 16. What would insufficient strength in a dental amalgam lead to? a. Tarnish b. Fracture c. Expansion d. Condensation ANS: B

A B C D

Feedback Tarnish is a surface reaction. Insufficient strength may lead to bulk fracture or marginal fracture requiring replacement. Some expansion and contraction is expected during the setting phases. Condensation relates to placement.

DIF: Knowledge REF: p. 61 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 17. Which of the following statement(s) is(are) true of the property of creep for amalgam

restorations? a. High-copper amalgams have values of creep far above old low-copper amalgams. b. It is associated with the breakdown of marginal integrity. c. The ANSI/ADA requires that creep be less than 3%. d. A, B, and C are true. e. B and C are true. ANS: E

A B C D E

Feedback High-copper amalgams have values of creep far below old low-copper amalgams and the ANSI/ADA limits. Creep is associated with the breakdown or marginal integrity, and the ANSI/ADA requires that creep be less than 3%. Creep is associated with the breakdown or marginal integrity, and the ANSI/ADA requires that creep be less than 3%. A and C are correct answers. A and C are correct answers.

DIF: Knowledge REF: p. 64 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a.

amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 18. What is tarnish? a. A surface phenomenon b. Equivalent to corrosion c. A destructive process that eventually leads to failure of the restoration d. The result of chemical reactions that penetrate into the body of the amalgam ANS: A

A B C D

Feedback Tarnish is a surface phenomenon. Corrosion and tarnish are both prominent reactions of dental amalgam. Corrosion is the result of chemical reactions that penetrate into the body of the material and eventually lead to failure of the restoration. Corrosion is the result of chemical reactions that penetrate into the body of the material and eventually lead to failure of the restoration.

TrEthSeTmBaAnN .aClgOaMm? 19. What is the correct order fo ipK ulS atEioLnLoE fR am a. Carving, condensation, mixing, and finishing b. Condensation, finishing, mixing, and carving c. Mixing, condensation, carving, and finishing d. Mixing, finishing, condensation, and carving ANS: C

A B C D

Feedback These tasks are out of order and not viable. These tasks are out of order and not viable. The correct order for manipulation of amalgam is mixing, condensation, carving, and finishing. These tasks are out of order and not viable.

DIF: Analysis REF: p. 66 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 20. How will under-triturated amalgam appear? a. Dull

b. c. d. e.

Soupy Crumbly A and C B and C

ANS: D

A B C D E

Feedback Under-triturated amalgam is dull and crumbly. Over-triturated amalgam is wet or soupy. A and C are correct answers. A and C are correct answers. A and C are correct answers.

DIF: Knowledge REF: p. 66 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 21. Why are ultrasonic condensers discouraged for condensation of amalgam? a. Increase the evaporation of mercury from the setting amalgam b. Provide insufficient condensation force c. Apply excessive condensation forces d. Traumatize the dental pulp ANS: A

A B C D

Feedback Ultrasonic condensers are discouraged because they increase the evaporation of mercury from the setting amalgam. Ultrasonic condensers are discouraged because they increase the evaporation of mercury from the setting amalgam. Ultrasonic condensers are discouraged because they increase the evaporation of mercury from the setting amalgam. Ultrasonic condensers are discouraged because they increase the evaporation of mercury from the setting amalgam.

DIF: Knowledge REF: p. 67 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 22. Which of the following is the most likely route of entry for mercury into the patient and dental

personnel during the manipulation of amalgam? a. Absorption in the gut b. Contact through skin c. The lungs as a vapor

d. Intraoral absorption ANS: C

A B C D

Feedback Gut absorption is a route for exposure, but it is less common when good mercury hygiene is used. Skin may be a route for exposure, but it is less common when good mercury hygiene is used. The most likely route of entry of mercury into the patient and dental personnel is through the lungs as a vapor. Intraoral absorption is a route for exposure, but it is less common when good mercury hygiene is used.

DIF: Knowledge REF: p. 69 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 23. How should amalgam scrap be handled? a. Flushed down the drain with ample water b. Stored in a sealed container in the refrigerator c. Disposed of in the trash with other daily refuse d. Stored in a sealed container containing x-ray developer e. Stored in a sealed container containing x-ray fixer or another reducing agent

TESTBANKSELLER.COM

ANS: E

D E

Feedback The office should have a comprehensive plan for mercury hygiene, including an amalgam separator to limit mercury efflux into the water waste. Scrap amalgam in the trash may end up in landfills and contaminate groundwater. The office should have a comprehensive plan for mercury hygiene, including an amalgam separator to limit mercury efflux into the water waste. Scrap amalgam in the trash may end up in landfills and contaminate groundwater. The office should have a comprehensive plan for mercury hygiene, including an amalgam separator to limit mercury efflux into the water waste. Scrap amalgam in the trash may end up in landfills and contaminate groundwater. Amalgam scrap should be stored in a sealed container containing x-ray fixer or another reducing agent. The office should have a comprehensive plan for mercury hygiene, including an amalgam separator to limit mercury efflux into the water waste. Scrap amalgam in the trash may end up in landfills and contaminate groundwater.

DIF: Application REF: p. 69 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of

materials 24. The maximum permittable mercury vapor level established by OSHA is

mg/m per

40-hour week. a. 0.05 b. 0.5 c. 5 d. 50 ANS: A

A B C D

Feedback The maximum permittable mercury vapor level established by OSHA is 0.05 mg/m per 40-hour week. That limit is well above established OSHA guidelines. That limit is well above established OSHA guidelines. That limit is well above established OSHA guidelines.

DIF: Knowledge REF: p. 69 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 25. When should high-volume evacuation be used with dental amalgam? a. Placing b. Polishing c. Removing d. Doing all of the above ANS: D

Feedback The use of high-volume evacuation during placement, polishing, and removal of amalgam restorations reduces the exposure of the patient and the dental team to mercury vapor. The use of high-volume evacuation during placement, polishing, and removal of amalgam restorations reduces the exposure of the patient and the dental team to mercury vapor. The use of high-volume evacuation during placement, polishing, and removal of amalgam restorations reduces the exposure of the patient and the dental team to mercury vapor. The use of high-volume evacuation during placement, polishing, and removal of amalgam restorations reduces the exposure of the patient and the dental team to mercury vapor.

DIF: Comprehension REF: p. 69 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 26. Which of the following statements is correct regarding today’s dental amalgam? a. It is high in zinc. b. It is low in copper. c. It has high longevity. d. It has placement issues. ANS: C

A B C

Feedback Today’s amalgams are low in zinc or zinc free. Today’s amalgams are high in copper. Amalgam is a viable clinical choice where longevity, ease of placement, and clinical performance are paramount, especially when clinical conditions are challenging. Today’s amalgams work well in difficult placement challenges.

DIF: Knowledge REF: p. 58 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 27. At 1 day after placement, amalgam’s tensile strength most closely resembles which human

structure? a. Bone b. Dentin c. Enamel d. Cementum ANS: B

A B C D

Feedback The strengths of bone and cementum are similar. The tensile strength of amalgam at 1 day is approximately the same as human dentin. Enamel is harder than dentin. The strengths of bone and cementum are similar.

DIF: Knowledge REF: p. 61 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 28. On average, how much copper is in today’s dental alloy? a. 4%

b. 10% c. 20% d. 50% ANS: C

A B C

Feedback This is lower than the average amount used in today’s dental alloy. This is lower than the average amount used in today’s dental alloy. Historically, the silver alloy used in dental amalgams had low (2 to 4 wt %) amounts of copper. These alloys were combined with mercury to form low-copper amalgam. However, the development of silver alloys with higher (13% to 30%, generally about 20%) copper has replaced low-copper alloys, because high-copper alloys produce amalgams with higher strength, less corrosion, less creep, and better longevity at the margins. This is an excessive amount of copper and would not be considered.

DIF: Knowledge REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 29. Which of the following is incorrect regarding admixed alloy? a. It makes better proximal contacts. b. It is a mixture of particT leE s.STBANKSELLER.COM c. It is easy to condense. d. It is easier to carve. ANS: B

A B

C D

Feedback This is a correct statement. If a mixture of particles is used, the alloy is referred to as an admixed alloy. Amalgams containing irregular particles with or without spherical particles added require greater packing or condensation forces during placement than amalgams with spherical particles alone. Most practitioners feel that amalgams containing irregular particles produce better proximal contacts and are easier to carve. This is a correct statement. This is a correct statement.

DIF: Knowledge REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 30. Which of the following is incorrect regarding spherical alloy?

a. b. c. d.

It is easy to condense. It sets faster than admixed amalgam. It requires more mercury than admixed amalgam. It makes better proximal contacts than admixed amalgam.

ANS: A

B C D

Feedback Spherical amalgams require less mercury and set somewhat faster than admixed amalgams. Practitioners generally select either a spherical or admixed amalgam, depending on the clinical situation. The importance of proper manipulation of each type cannot be overemphasized. For example, if a condensation force that is appropriate for a spherical amalgam is applied to an admixed amalgam, the restoration will likely contain voids and lack adequate proximal contacts. This is a correct statement. This is a correct statement. This is a correct statement.

DIF: Comprehension REF: p. 59 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 31. Mercury is liquid at room temperature. It is one of two liquid metallic elements on the

periodic table. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is incorrect. d. Statement 1 is incorrect; statement 2 is correct. ANS: B

A B C D

Feedback Statement 1 is correct, and statement 2 is incorrect. Mercury is a dense metal (density = 13.5 g/mL) and the only metallic element in the periodic table that is a liquid at room temperature. Statement 1 is correct, and statement 2 is incorrect. Statement 1 is correct, and statement 2 is incorrect.

DIF: Comprehension REF: p. 59 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 32. Which of the following is a correct assessment regarding mercury vapor in amalgam? a. Higher release may occur during the setting reaction. b. Higher release may occur during removal of old amalgams.

c. Higher release may occur if the amalgam is heated above 80° C. d. All of the above are correct statements. ANS: D

A B C D

Feedback A, B, and C are all correct statements. A, B, and C are all correct statements. A, B, and C are all correct statements. Higher release may occur during the setting reaction, during removal of old amalgams, or if the amalgam is heated above 80° C.

DIF: Comprehension REF: p. 60 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 33. The sum of

determines the overall dimensional change of an amalgam restoration. a. compressive strength plus condensation b. contraction and expansion during setting c. compressive strength plus tensile strength d. the amount of tarnish and corrosion produced ANS: B

A B

C D

Feedback The strength of an amalgam must withstand oral forces. Insufficient strength may lead to bulk fracture or marginal fracture requiring replacement. Although it is somewhat confusing, expansion and contraction occur simultaneously during the setting reaction of amalgam. The dissolution of the alloy particles into the liquid mercury generally leads to contraction, whereas the formation of matrix products causes expansion. The overall dimensional change is therefore the sum of these two processes. When amalgam restorations are subjected to occlusal forces in service, both compressive and tensile stresses result in an amalgam restoration. Tarnish is a surface reaction, and corrosion eventually causes the restoration to fail.

DIF: Knowledge REF: p. 63 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 34. How will the mixture appear if amalgam is over-triturated? a. Puttylike consistency b. Dry, crumbly mix

c. Wet, soupy mix d. Hard ball ANS: C

A B C

Feedback A is the result of proper trituration of the material. B is the result of under-triturating the material. Over-triturated amalgam is soupy and adheres to the inside of the capsule. It will have poorer strength and creep and may have poorer corrosion properties, all caused by over-formation of the matrix products. Hard ball is the result of allowing the material to stand too long unused.

DIF: Knowledge REF: p. 66 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 35. Which of the following are characteristics of under-triturated amalgam? a. Will appear dry and crumbly b. Does not condense well c. Is shiny in appearance d. A and B are correct. ANS: D

A B C D

Feedback Under-triturated amalgam is dry and crumble in appearance. Under-triturated amalgam is more difficult to condense. Under-triturated amalgam has a dull, crumbly appearance. A and B are correct.

DIF: Knowledge REF: p. 66 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 36. Amalgam should be placed in the cavity preparation by a. large to small b. consistent size c. small to large

increments.

ANS: C

A B

Feedback Large increments placed initially may leave voids in the mass. Amalgam should be placed in small increments first to ensure proper

condensation. The assistant selects the end of the instrument appropriate for the clinical needs as directed by the operator; generally, smaller increments are used initially, graduating to larger increments.

DIF: Knowledge REF: p. 67 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 37. What is the purpose of over-packing the preparation with amalgam? a. Adequate contour b. Correct occlusion c. Closed margins d. All of the above ANS: D

A B C D

Feedback A, B, and C are all correct answers. A, B, and C are all correct answers. A, B, and C are all correct answers. The cavity preparation is always over-packed with amalgam and carved back to final contours. Over-packing allows the practitioner to control the final shape and occlusion of the rT esEtoSraTtiBoA nN mK ore loL seElyRt. haCnOwMould be possible otherwise. SEcL

DIF: Knowledge REF: p. 67 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 38. Why is it important to use water when polishing an amalgam restoration? a. Assures integrity of the enamel b. Produces a high glossy finish c. So the tooth won’t overheat d. Insures smooth margins ANS: C

A B C

Feedback Enamel integrity is compromised by using highly abrasive materials. A glossy finish is achieved by using abrasive polishes. Polishing always should be done wet (with water), because dry polishing may overheat the amalgam and tooth. Overheating may damage the pulp of the tooth and the amalgam surface by driving mercury from the amalgam. Margins are smoothed using abrasive stones or finishing burs to marginate the restoration.

DIF: Knowledge REF: p. 68 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 39. Which of the following is a component of good mercury hygiene? a. Using a squeeze cloth to remove excess mercury b. Using premixed, sealed capsules c. Handling it only with gloves on d. Polishing using a dry technique ANS: B

A B C D

Feedback Premeasured capsules eliminate the need to remove excess mercury. The use of precapsulated amalgam limits handling of liquid mercury and reduces the possibility of a spill of liquid mercury in the office. Mixed amalgam should never be touched, even with gloved hands. Polishing should be done in a wet environment to reduce mercury vapor.

DIF: Knowledge REF: p. 69 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam TgESSuT MSC: NMDHE, 6.0 Providin ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceMs, 6.1 Properties and manipulation of materials 40. Which component added to silver alloy causes amalgam to expand if contaminated by saliva? a. Mercury b. Copper c. Zinc d. Tin ANS: C

A B C

Feedback Mercury does not cause the material to expand. Copper does not cause the material to expand. Historically, amalgams that contained zinc expanded sufficiently to fracture the tooth if they were contaminated with moisture during placement. The expansion occurred slowly over months after placement; restorations sometimes appeared to bulge out of the cavity preparation. Zinc is no longer used in silver alloy. Tin does not cause the material to expand.

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 41. Of the following, which is an advantage of using spherical amalgam particles? a. Uses less mercury b. Easier to condense c. Sets slower for additional working time d. Produces a better interproximal contact ANS: A

A B C D

Feedback Spherical alloy requires less mercury. Irregular alloy is easier to condense. Spherical alloy sets faster. Spherical alloy provides a better interproximal contact.

DIF: Comprehension REF: p. 58 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials SHORT ANSWER 1. Compare and contrast corrT osEioSnTaB ndAtNaK rnS isE h.LLER.COM ANS:

Tarnish is a surface phenomenon that can result in a discolored restoration (Table 5-2). With tarnish, the chemical reaction between the amalgam and the oral cavity is restricted to the amalgam surface. Corrosion results from chemical reactions that penetrate into the body of the amalgam (Table 5-2). Although tarnish may be undesirable esthetically, it will not often cause a restoration to fail. Corrosion, on the other hand, eventually leads to failure of the restoration. Tarnish and corrosion occur more on amalgams with rough surfaces. Thus, a well-polished amalgam limits these problems. DIF: Knowledge REF: p. 65 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 2. Identify the three types of mercury and explain how each is acquired. ANS:

Mercury occurs in three forms: elemental (Hg0), inorganic (Hg2+), and organic. Each of these forms has different dynamics of entry into and excretion from the body. Furthermore, we are exposed to the different forms from different sources. For example, the most common source of organic forms is fish. In general, the organic forms are the most toxic because they are most efficiently distributed to long-term storage sites in the nerve and fat tissues. Exposure to inorganic mercury is less critical because it is poorly absorbed. DIF: Knowledge REF: p. 69 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 3. Compare and contrast expansion and contraction of a newly mixed amalgam. ANS:

Ideally, a freshly mixed amalgam would neither expand nor contract as it sets after it is condensed into a cavity preparation. Expansion may result in post-placement sensitivity or even protrusion from the cavity, whereas contraction would leave gaps between the restoration and the tooth prone to leakage and recurrent decay. DIF: Knowledge REF: p. 63 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. amalgam MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

Chapter 06: Finishing, Polishing, and Cleansing Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Why are finishing and polishing techniques so important in restorative dentistry? a. Remove excess material and to smooth roughened surfaces b. Remove plaque and calculus from restorations c. Burnish the margins of gold castings d. Work-harden metal surfaces ANS: A

A B C D

Feedback Finishing and polishing techniques are meant to remove excess material and to smooth roughened surfaces. Removal of biofilm and calculus from tooth surfaces is part of the prophylaxis process. The margins of gold castings are made accurate during the construction phase in the laboratory. Materials are polished once they have reached their full hardness either through chemical set or light cure.

DIF: Comprehension REF: p. 73 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. SelT ecEt S anT dB deAsN crK ibS e hEoL wLtoEm ipO ulM ate the various finishing, polishing, and Ra.nC cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 2. Which types of materials are used for finishing and polishing? a. Surfactants b. Humectants c. Astringents d. Abrasives ANS: D

A B C D

Feedback Surfactants lower surface tension. Humectants provide hydration. Astringents help control bleeding. The materials used for finishing and polishing are primarily abrasives.

DIF: Knowledge REF: p. 74 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth

3. For an abrasive, the higher the speed, the greater the frequency per unit of time the particle

contacts the surface. In a clinical situation it is easiest to control pressure rather than speed to vary the rate of abrasion. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Heavy pressure applied will cause deeper abrasions. Increasing speed increases the rate of abrasion. Heavy pressure applied will cause deeper abrasions. Increasing speed increases the rate of abrasion. In a clinical situation it is easiest to control speed rather than pressure to vary the rate of abrasion. Heavy pressure applied will cause deeper abrasions. Increasing speed increases the rate of abrasion.

DIF: Comprehension REF: p. 74 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 4. Which types of abrasives aT reEgSeT neBraAlly arR se.aCbO raM sives used primarily for the NKhSarEd,LcLoE

development of desired contours of a restoration or tooth preparation and for the removal of gross irregularities on a surface? a. Cleansing b. Finishing c. Polishing d. A and B e. B and C ANS: B

A B

C D E

Feedback Cleansing abrasives are soft materials. Finishing abrasives are generally hard, coarse abrasives used primarily for the development of desired contours of a restoration or tooth preparation and for the removal of gross irregularities on a surface. Polishing abrasives have finer particle sizes and are generally less hard than abrasives that are used for finishing. A is incorrect, and B is correct. B is correct, and C is incorrect.

cleaning agents.CDA, GC, III Chairside Dental Materials (Preparation, Manipulation and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 5. Which abrasive disks are beige? a. Aluminum oxide b. Silicon carbide c. Garnet d. Cuttle ANS: D

A B C D

Feedback Aluminum oxide is used in air abrasion. Disks are reddish brown. Silicon carbide is the second hardest of the dental abrasives. Disks are black. Garnet is an abrasive that is mined. Disks are red. Cuttle abrasive disks are beige.

DIF: Knowledge REF: p. 75 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 6. Sand disks should not be used interchangeably with a. cuttle

disks.

b. diamond c. silicon carbide d. aluminum oxide ANS: A

A B C D

Feedback Sand disks should not be used interchangeably with cuttle disks. Diamond may be used with sand disks. Silicon carbide may be used with sand disks. Aluminum oxide may be used with sand disks.

DIF: Knowledge REF: p. 75 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 7. Which of the following abrasive agents commonly used in dentistry for polishing and

cleansing is derived from diatoms? a. Kieselguhr b. Calcite c. Pumice d. Rouge

ANS: A

A B C D

Feedback Kieselguhr is derived from diatoms, the remains of minute aquatic plants. Pumice is siliceous volcanic glass. Calcite is a form of calcium carbonate. Rouge is composed of iron oxide.

DIF: Knowledge REF: p. 75 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 8. Which of the following statements is true when using abrasives? a. The area being finished and polished should be rinsed with each successive change

of abrasive. b. Dry polishing will increase the danger of overheating the surface. c. Dry polishing will increase the efficiency of the abrasive. d. Both A and C are correct statements. ANS: D

A B C D

Feedback With each successive change in abrasive, the area being finished and polished is rinsed to remove the previously used abrasive particles. Dry polishing will incTreEaS seTtB heAdNaK ngSeE rL ofLthEeRt. ooCthOoMverheating and could damage the pulp. Dry polishing may reduce dramatically the efficiency of the abrasive. Both A and B are correct statements.

DIF: Comprehension REF: p. 76 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 9. Which of the following would represent an appropriate sequence for finishing and polishing

an amalgam restoration? a. Finishing bur, green stone, tin oxide, silex b. Green stone, finishing bur, silex, tin oxide c. Green stone, finishing bur, tin oxide, silex d. Tin oxide, silex, green stone, finishing bur ANS: B

Feedback Polishing in these cases is done through the application of a sequence of operations that includes the use of fine stones and abrasive disks or strips. The final polish is developed by the application of extra-fine silex, followed by the

B C

application of a thin slurry of tin oxide, with a rotating soft brush. Green stone, finishing bur, silex, and tin oxide represent an appropriate finishing and polishing sequence from coarse to fine. Polishing in these cases is done through the application of a sequence of operations that includes the use of fine stones and abrasive disks or strips. The final polish is developed by the application of extra-fine silex, followed by the application of thin slurry of tin oxide, with a rotating soft brush. Polishing in these cases is done through the application of a sequence of operations that includes the use of fine stones and abrasive disks or strips. The final polish is developed by the application of extra-fine silex, followed by the application of a thin slurry of tin oxide, with a rotating soft brush.

DIF: Application REF: p. 78 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 10. Some fast-setting, high-copper amalgams can be polished about 8 to 12 minutes after

placement with a a. dry; silex b. dry; tin oxide c. creamy; silex d. creamy; tin oxide

paste of extra-fine

and water in a rubber cup.

ANS: C

A B C D

Feedback Dry materials build up excessive heat that may damage the pulp. Dry materials build up excessive heat that may damage the pulp. Tin oxide is a fine white powder that is used as a final polishing agent. Some fast-setting, high-copper amalgams can be polished about 8 to 12 minutes after placement with a creamy paste of extra-fine silex and water in a rubber cup. Tin oxide is a fine white powder that is used as a final polishing agent.

DIF: Comprehension REF: p. 76 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 11. Which technique will produce the smoothest surface on a composite restoration? a. Curing against a polyester matrix b. Twelve-blade carbide burs c. Diamond stones d. Green stones e. White stones ANS: A

Feedback

A B C D E

The smoothest surface on a composite restoration is produced by curing against a polyester matrix. Twelve-blade carbide burs are used to remove gross amounts of material from the marginal areas. Diamond is used to remove gross amounts of material from the marginal areas. Stones are used to finish areas that are difficult to access. Stones are used to finish areas that are difficult to access.

DIF: Comprehension REF: p. 77 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 12. Which technique will produce the smoothest surface of a gold casting? a. Chamois b. Fine cuttle disk c. Crocus disk with rouge d. Polished wax, pickled casting ANS: C

A B C D

Feedback Chamois is a soft cloth that would need a light abrasive material, rouge, in order to work adequately. A cuttle disk is too abrasive. The smoothest surfacT eE ofSaTgB olAdNcK asS tiE ngLcLaE nR be.pCrO odMuced using a crocus disk with rouge. A casting is pickled immediately after casting to remove surface impurities.

DIF: Knowledge REF: p. 77 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 13. Which of the following represents an appropriate sequence for finishing and polishing an

acrylic denture base? a. Pumice slurry, finishing bur, tripoli b. Pumice slurry, tripoli, finishing bur c. Finishing bur, tripoli, pumice slurry d. Finishing bur, pumice slurry, tripoli e. Tripoli, finishing bur, pumice slurry ANS: D

Feedback The elements in this answer are out of order. Each element should be of a less abrasive quality than the one before, with the finishing bur as the most abrasive element.

The elements in this answer are out of order. Each element should be of a less abrasive quality than the one before, with the finishing bur as the most abrasive element. The elements in this answer are out of order. Each element should be of a less abrasive quality than the one before, with the finishing bur as the most abrasive element. A finishing bur, pumice slurry with a single-row brush wheel or rag wheel, and a final high polish with a rag wheel with tripoli, bendick, or a paste of tin oxide and water is an appropriate finishing sequence for polishing an acrylic denture base. The elements in this answer are out of order. Each element should be of a less abrasive quality than the one before, with the finishing bur as the most abrasive element.

DIF: Application REF: p. 78 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 14. After polishing, a denture should be stored a. dry b. moist c. in glycerin d. in ultrasonic cleaning solution

until delivery to the patient.

ANS: B

A B C D

Feedback Denture material will dry out if not kept moist with water. This can cause warping and shrinking of the acrylic. After polishing, a denture should be stored moist until delivery to the patient. Glycerin is not an appropriate material to store a denture in. Ultrasonic cleaning solution is not an appropriate material to store a denture in.

DIF: Knowledge REF: p. 78 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 15. Which of the following procedures are recommended in order to maintain infection control

when using pumice to polish acrylic denture base material? a. Change pumice daily. b. Use a separate pumice pan for each patient. c. Mix pumice with a liquid disinfectant such as 5 parts sodium hypochlorite to 100 parts distilled water. d. A, B, and C are all recommended. e. Only A and C are recommended. ANS: D

A B C D E

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. All three are recommended. Use a separate pumice pan for each patient; mix pumice with a liquid disinfectant; and change the pumice daily. A, B, and C are all correct.

DIF: Comprehension REF: p. 78 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 16. Which of the following types of abrasive materials found in prophy paste, wear during use but

continue to abrade, producing an increasingly smoother surface? a. Perlite b. Silicon dioxide c. Zirconium silicate d. Diatomaceous silicon dioxide e. Sodium-potassium-aluminum silicate ANS: A

A B C D E

Feedback Perlite wears during uTseE. S ATs B thAeNpK arS ticEleLsLwEeR ar. , tChO eyMbecome smaller but continue to abrade, producing an increasingly smoother tooth surface. Silicon dioxide is a polishing agent that could damage tooth structure with overuse. Zirconium silicate is a polishing agent that could damage tooth structure with overuse. Diatomaceous silicon dioxide is a polishing agent that could damage tooth structure with overuse. Sodium-potassium-aluminum silicate is a polishing agent that could damage tooth structure with overuse.

DIF: Knowledge REF: p. 78 OBJ: 10 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 17. Which of the following restorative materials is most subject to wear during a prophylactic

procedure? a. Resin composites b. Dental amalgam c. Cast gold d. Ceramic

ANS: A

A B C D

Feedback Resin composites are most subject to wear, because of the low hardness of the resin. Amalgam does not easily wear. Cast gold will abrade if coarse abrasives are used. Ceramic materials do abrade if coarse abrasives are used.

DIF: Knowledge REF: p. 78 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 18. Which of the following materials is the most difficult to remove from a tooth surface during

tooth prophylaxis? a. Acquired pellicle b. Food debris c. Calculus d. Plaque ANS: C

A B C D

Feedback Soft deposits can be easily removed during a prophylaxis. Soft deposits can be eT asEilS yTreBmAoN veKdSdEuL rinLgEaRp.roCpOhM ylaxis. Calculus is the most difficult to remove from a tooth surface during tooth prophylaxis. Soft deposits can be easily removed during a prophylaxis.

DIF: Knowledge REF: p. 80 OBJ: 14 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 19. What is the purpose of a humectant in toothpaste? a. Prevent dehydration b. Function as a binder c. Prevent dental caries d. Function as an abrasive e. Reduce the rate of formation of supragingival calculus ANS: A

A B C

Feedback The purpose of a humectant in toothpaste is to prevent dehydration. Binders are an additive. Fluorides help prevent caries.

D E

Abrasives help remove stain. Tetrasodium pyrophosphates reduce the rate of calculus formation.

DIF: Knowledge REF: p. 80 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 20. Which of the following is not one of the criteria for an ideal denture cleanser? a. Be stable during storage b. Preferably be bactericidal and fungicidal c. Be able to remineralize worn acrylic denture teeth d. Be able to attack or dissolve both the organic and inorganic portions of denture

deposits ANS: B

A B C D

Feedback This is a positive quality of a denture cleanser. This is a positive quality of a denture cleanser. Being able to remineralize worn acrylic denture teeth is not one of the criteria for an ideal denture cleanser. This is a positive quality of a denture cleanser.

DIF: Comprehension REF: p. 80 OBJ: 21 TOP: CDA, GC, III ChairsiT deEDSeT ntB alAMNaK teS riaElsL(L PrE epRa. raC tioOnM , Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Which of the following choices represent(s) an effective means of improving denture

cleanliness? a. Fifteen-minute soaking b. Ultrasonic vibration c. Chemical cleansers d. Brushing e. C and D ANS: E

A B C D E

Feedback Fifteen-minute soaking is neither effective on mature plaque nor completely effective on stains and deposits. Ultrasonic vibration is not an efficient method for removal of denture plaque. Both C and D are correct. Both C and D are correct. Brushing of a denture surface and chemical cleansers are effective means of improving denture cleanliness and maintaining a healthy mucosa beneath a removable partial denture.

appliances fabricated from base metals such as cobalt-chromium alloy? a. Light brushing b. Soaking in hot water c. Immersion in a solution containing 1 teaspoon of a hypochlorite (Clorox) and 2 teaspoons of a glassy phosphate (Calgon) in one-half glass of water d. A, B, and C e. A and C ANS: A

A B C

D E

Feedback Light brushing is recommended. Dentures should not be soaked in hot water, because the heat may cause the acrylic to become distorted. Immersion in a solution containing 1 teaspoon of a hypochlorite (Clorox) and 2 teaspoons of a glassy phosphate (Calgon) in one-half glass of water is not recommended for use on prosthetic appliances fabricated from base metals such as cobalt-chromium alloy, because chlorine solutions tend to darken these metals. Only A is correct. Only A is correct.

DIF: Comprehension REF: p. 81 OBJ: 23 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Which of the following methods would not be used to clean a denture with a soft liner? a. Cotton under cold water b. A brush with hard, stiff bristles c. A soaking type of denture cleanser d. An organic solvent such as chloroform e. Immersion in sodium hypochlorite followed by light brushing ANS: D

A B C D E

Feedback The soft liner should be cleaned with cotton under cold water. Soft liner is a fragile material that could be damaged by a stiff brush. Denture cleanser may be absorbed into the soft liner. Chloroform is toxic if ingested. Sodium hypochlorite is toxic if ingested.

DIF: Knowledge

REF: p. 81

OBJ: 23

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. Home bleaching agents typically contain 10% to 22% a. carbamide b. hydrogen c. calcium d. sodium

peroxide.

ANS: A

A B C D

Feedback Home bleaching agents typically contain 10% to 22% carbamide peroxide. Hydrogen peroxide is used for in-office bleaching. Calcium is used to assist with remineralization during treatment. Sodium is not used in bleaching materials.

DIF: Knowledge REF: p. 81 OBJ: 27 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 2. Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. bleaching agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. Which of the following statements is true of bleaching agents? a. They will adversely affect restorative materials such as gold alloys, amalgam,

microfilled composites, or porcelain.

ER b. Some microhybrid comTpE osSitTesB, A hyNbKriS dEioLnL om er. s,CanOdMglass ionomers have been roughened slightly by bleaching gels. c. Bleach should come in contact with dentin in order to bleach the yellow shade. d. Yellow, orange, or light brown stains are the least responsive to bleaching. ANS: B

A B C D

Feedback Bleaching agents typically do not affect gold alloys, amalgams, composites, or porcelain. Some microhybrid composites, hybrid ionomers, and glass ionomers have been roughened slightly by bleaching gels. Contact with dentin may cause hypersensitivity. Bleaching agents are effective against yellow, orange, and light brown stains.

DIF: Comprehension REF: p. 81 OBJ: 28 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 2. Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. bleaching agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. Which factor affects the rate of abrasion? a. Rate of speed b. Type of material

c. Depth of the material d. Number of filler particles ANS: A

C D

Feedback The rate of abrasion of a given material by a given abrasive is determined primarily by three factors: the size of the abrasive particle, the pressure of the abrasive against the material being abraded, and the speed at which the abrasive particle moves across the surface being abraded. All these factors can be controlled clinically. The rate of abrasion of a given material by a given abrasive is determined primarily by three factors: the size of the abrasive particle, the pressure of the abrasive against the material being abraded, and the speed at which the abrasive particle moves across the surface being abraded. All these factors can be controlled clinically. There is significance in placement of the material but not on the rate of abrasion. The rate of abrasion of a given material by a given abrasive is determined primarily by three factors: the size of the abrasive particle, the pressure of the abrasive against the material being abraded, and the speed at which the abrasive particle moves across the surface being abraded. All these factors can be controlled clinically.

DIF: Knowledge REF: p. 74 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 27. When using an abrasive material how will the amount of pressure exerted affect the outcome? a. Cause the material to fracture if excessive b. Cause the finish to be glossy as it increases c. Cause deeper grooves in the finished restoration d. Eliminate intrinsic stains in the surrounding enamel ANS: C

A B C D

Feedback The polishing disk or wheel may fracture. Excess pressure will scratch the surface of the restoration. Heavy pressure applied by the abrasive causes deeper scratches and more rapid removal of material. Abrasives do not remove intrinsic stains.

a. b. c. d.

Allows stain formation Reduces retention of bacteria Increases retention of bacteria Produces a dull, nonreflective appearance

ANS: A

A B C D

Feedback A smooth surface prevents the formation of stains. A smooth surface (Ra less than 0.2 m) will reduce retention of bacteria and give the restoration a shiny appearance. A smooth surface will reduce retention of bacteria. The smooth surface produces a shiny appearance.

DIF: Knowledge REF: p. 76 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 29. What are the three categories of abrasives used in dentistry? a. Tin oxide and rouge b. Light, medium, and coarse pumice c. Smoothing, wearing, and adhering d. Finishing, polishing, and cleansing ANS: D

A B C D

Feedback All are grits of abrasive materials. All are types of abrasive materials. Abrasives remove excess material including biofilms that adhere to the tooth surface. The three categories of abrasives used in dentistry are finishing, polishing, and cleansing abrasives.

DIF: Comprehension REF: p. 74 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 30. What is the purpose of using glycerin with polishing agents? a. Maintains consistency b. Improves polish c. Provides gloss d. Evaporates ANS: A

Feedback

A B C D

The use of glycerin as a medium prevents the change in consistency that occurs when water, which evaporates, is used to make a slurry. The use of glycerin as a medium prevents the change in consistency that occurs when water, which evaporates, is used to make a slurry. The use of glycerin as a medium prevents the change in consistency that occurs when water, which evaporates, is used to make a slurry. The use of glycerin as a medium prevents the change in consistency that occurs when water, which evaporates, is used to make a slurry.

DIF: Knowledge REF: p. 75 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 31. Which of the following is true about diamond stones? a. Chips added to a binder b. Cannot produce fine detail c. Formed into disks, cups, or points d. A, B, and C are all correct. e. Only A and C are correct. ANS: E

A B C D E

Feedback Diamond chips normally are impregnated in a binder to form diamond stones and disks. Diamond stones are made in different abrasive rates, and the fine and extra-fine can produce a smooth, detailed surface. Diamond stones may be formed into disks, cups, and points made with microfine diamonds. Only A and C are correct. Only A and C are correct.

DIF: Comprehension REF: p. 75 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 32. When are fine abrasives used? a. Reduce scratches b. Contour the restoration c. Remove excess material d. Provide detailed anatomy ANS: A

Feedback Successively finer abrasives remove the large scratches produced.

B C D

Restorations are contoured using more abrasive burs and stones. Excess material is removed using more abrasive burs and stones. Most of the detailed anatomy is placed when the material is carved and then refined with lighter abrasives.

DIF: Knowledge REF: p. 76 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 33. At what point can high-copper amalgams be polished? a. Should not be polished b. Can be polished after 8 to 12 minutes c. Should be polished after 24 hours ANS: B

A B C

Feedback Polishing an amalgam restoration smooths rough surfaces. Some of the fast-setting high-copper amalgams can be polished about 8 to 12 minutes after placement because of their rapid development of strength. Conventional amalgams must set 24 hours before polishing.

DIF: Knowledge REF: p. 76 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. SelT ecEt S anT dB deAsN crK ibS e hEoL wLtoEm ipO ulM ate the various finishing, polishing, and Ra.nC cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 34. Which statement is correct about the finish on a glass ionomer restoration? a. Rougher than a compomer b. The same as composite resin c. Smoother than a compomer d. Smoother than composite resin ANS: A

B C D

Feedback The roughness of finished and polished glass ionomer restorations is higher than that of composites and resin-modified glass ionomers, primarily because of the larger particle sizes of the filler. Compomer and composite resin will finish smoother than glass ionomer. Compomer and composite resin will finish smoother than glass ionomer. Compomer and composite resin will finish smoother than glass ionomer.

35. Which of the following is true about rag wheels and pumice? a. Disposed of after each patient use b. Sterilized before the next patient use c. Used on the tongue side of the prosthetic d. Only A and B e. All of the above ANS: D

A B C D

Feedback A and C are both correct. Rag wheels can be sterilized, but pumice should not be used on other patients. A and C are both correct. A rag wheel and felt cone with pumice slurry are used to finish the tongue side of a maxillary base. To maintain infection control, separate polishing burs, rag wheels, and pumice pans should be used for prostheses. Only A and B are correct.

DIF: Knowledge REF: p. 78 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. Dentifrice products that contain pumice and quartz show lower cleansing values. Dentifrice

products that contain pumice and quartz show lower abrasion to tooth surfaces. a. Statement 1 is correct; T stE atS em enAt N 2K isScE orL reLctE. R.COM TB b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

A B C D

Feedback Both statements are incorrect. Both statements are incorrect. Both statements are incorrect. Products that contain predominantly pumice and quartz show higher cleansing values but generally result in a greater abrasion to both enamel and dentin.

DIF: Comprehension REF: p. 78 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth 37. Which of the following cleaning techniques would be most effective for cleaning stain and

plaque from dentures? a. A 15-minute soak daily with a chemical tablet b. Using a toothbrush and fluoridated toothpaste c. Periodic immersions in an ultrasonic cleaner

d. Using a denture brush and denture paste ANS: D

A B C D

Feedback Customary 15-minute soaking is neither effective on mature plaque nor completely effective on stains and deposits. The patient should be cautioned not to use dentifrices for cleansing denture bases or acrylic denture teeth. Ultrasonic vibration is not an efficient method for removal of denture plaque. The brushing of a denture surface is an effective means of improving denture cleanliness and maintaining a healthy mucosa beneath a removable denture.

DIF: Comprehension REF: p. 81 OBJ: 23 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. What are the side effects of tooth whitening procedures? a. Lightening esthetic restorations b. Sloughing of the gingiva c. Tooth hypersensitivity d. All of the above e. Only B and C ANS: E

A B C D E

Feedback Whitening products do not adversely affect esthetic materials such as composite resin. B and C are both correct. B and C are both correct. Only A and C are correct. Side effects are uncommon but include tooth hypersensitivity, soft tissue lesions or sloughing, nausea, temporomandibular joint syndrome from the tray, and sore throats from swallowing the bleach.

DIF: Comprehension REF: p. 81 OBJ: 29 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39.

Which of the following is not part of the guidelines for in-office bleaching? Patients can be processing while the dental team is seeing other patients. The patient should have a comprehensive exam prior to the procedure. The patient should have a complete prophylaxis prior to the procedure. The patient may need local anesthetic for sensitivity. Both A and D are correct.

a. b. c. d. e.

ANS: E

A B C D E

Feedback Patients should not be left unattended during the procedure. This answer is part of the guidelines for in-office whitening procedures. This answer is part of the guidelines for in-office whitening procedures. Patients do not receive local anesthetic for in-office whitening procedures. Answers A and D are not part of the guidelines for in-office whitening procedures.

DIF: Comprehension REF: p. 82 OBJ: 33 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to c. composites MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. Which of the following is not a recommended type of denture cleaner? a. Abrasive creams b. Alkaline perborates c. Fluoridated toothpaste d. Alkaline hypochlorites ANS: C

A B C D

Feedback Abrasive creams are one of the three types of acceptable cleansers for cleaning dentures at home. Alkaline perborates are one of the three types of acceptable cleansers for cleaning dentures at home. Fluoridated toothpasteTsEaS reTtB ooAaNbK raS siE veLfLoE r dRe. ntCuO reMmaterials. In addition, fluoride is not needed for dentures. Alkaline hypochlorites are one of the three types of acceptable cleansers for cleaning dentures at home.

DIF: Comprehension REF: p. 81 OBJ: 22 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Whitening agents are effective in removing which type(s) of stain or discoloration? a. Tetracycline stain b. Black line stain c. Decalcification d. Coffee stain ANS: A

A B C D

Feedback Tetracycline is an intrinsic stain that is effectively treated with whitening agents. Black line stain is extrinsic and can be removed during a routine prophylaxis. Decalcification of enamel is best treated with a restorative material. Coffee stain is extrinsic and can be removed during a routine prophylaxis.

DIF: Comprehension REF: p. 81 OBJ: 26 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 2. Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. bleaching agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast in-office and home whitening materials. ANS:

Whitening agents used in the office commonly contain 30% to 35% hydrogen peroxide. One system mixes 35% hydrogen peroxide with silica to form a gel. Another system contains calcium, phosphate, and fluoride ions to allow remineralization during treatment. Home whitening products typically contain 10% to 22% carbamide peroxide or 1.5% to 6% hydrogen peroxide. The pH of these products ranges from 4.6 to 6.7 when undiluted and from 4.3 to 6.6 when diluted 1:2 with water. DIF: Comprehension REF: p. 81 OBJ: 27 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 2. Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. bleaching agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Explain the guidelines for helping a patient choose the correct dentifrice for his/her needs. ANS:

The best available guidelines to follow in selecting a dentifrice for a patient are based on evaluation of the following four factors: 1. Degree of staining of the dentition 2. Force exerted on the brush 3. Method of brushing 4. Amount of exposed dentin or cementum DIF: Comprehension REF: p. 80 OBJ: 20 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.2 Polishing natural and restored teeth

Chapter 07: Cements Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Cements are generally hard, brittle materials formed when a powdered

is mixed with a

liquid. a. quartz b. monomer c. acrylic resin d. oxide or glass ANS: B

A B C D

Feedback Quartz is used in composite resin materials. Monomer is used with a polymer, usually in an acrylic. Acrylic resins form from the polymerization process. Cements are generally hard, brittle materials formed when a powdered oxide or glass is mixed with a liquid.

DIF: Knowledge REF: p. 85 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing veKTSreEaL tmLeE ntRS. erC viO ceMs, 6.1 Properties and manipulation of TESSupp TBorAtiN materials 2. Which of the following is a strong cement that may be used for permanent restorations such as

crowns and bridges? a. Varnish b. Calcium hydroxide c. Zinc polycarboxylate d. Unreinforced zinc oxide–eugenol e. Unreinforced zinc oxide–noneugenol ANS: C

A B C D E

Feedback Varnish is a cavity liner. Calcium hydroxide is used as a low-strength liner/base. Zinc polycarboxylate is strong cement that may be used for permanent restorations such as crowns and bridges. Unreinforced zinc oxide–eugenol does not have the necessary strength for permanent cementation. Unreinforced zinc oxide–noneugenol does not have the necessary strength for permanent cementation.

DIF: Knowledge

REF: p. 85

OBJ: 1

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 3. Which of the following is oil-based cement? a. Glass ionomer b. Hybrid ionomer c. Zinc oxide–eugenol d. Zinc polycarboxylate ANS: C

A B C D

Feedback This is water-based cement. This is water-based cement. Zinc oxide–eugenol is oil-based cement. This is water-based cement.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 4. Which type of cement has T aE poSwTdBeA r cNoK mS pE osLedLoEfRa. luC mOinMosilicate glass? a. Zinc polycarboxylate b. Zinc oxide–eugenol c. Zinc phosphate d. Glass ionomer ANS: D

A B C D

Feedback This contains zinc in the powder. This contains zinc in the powder. This contains zinc in the powder. Glass ionomer contains a cement powder of finely ground aluminosilicate glass.

DIF: Knowledge REF: p. 85 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 5. Which type of cement, used for final cementation, has the highest compressive strength? a. Compomer b. Glass ionomer

c. Zinc phosphate d. Hybrid ionomer e. Zinc polycarboxylate ANS: B

A B C D E

Feedback Compomer has lower compressive strength (85 to 120 MPa). Glass ionomer has a compressive strength of 90 to 220 MPa, the highest of any of the listed cements. Zinc phosphate is rarely used because of its high acidity and exothermic reaction. Hybrid ionomer has lower compressive strength (85 to 120 MPa). Zinc polycarboxylate has a compressive strength of 55 to 96 MPa.

DIF: Knowledge REF: p. 87 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 6. Which of the following statements is(are) true regarding glass ionomer cements? a. Fluoride may be added to the powder for an anticariogenic effect. b. Some retention is gained through chemical bonding as well as mechanical

bonding. c. A calcium hydroxide bT asEeSisTnBoA t rNecKoSmEmLeL ndEeR d.wChO enMglass ionomer cement is used

in a deep cavity. d. A, B, and C are all true statements. e. A and B are both true statements. ANS: E

A B C D E

Feedback Fluoride is incorporated into the powder for an anticariogenic effect, and some retention is gained through chemical bonding as well as mechanical bonding. Fluoride is incorporated into the powder for an anticariogenic effect, and some retention is gained through chemical bonding as well as mechanical bonding. A calcium hydroxide base is recommended when glass ionomer cement is used in a deep cavity. Only A and B are correct. Fluoride is incorporated into the powder for an anticariogenic effect, and some retention is gained through chemical bonding as well as mechanical bonding.

DIF: Comprehension REF: p. 87 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

7. What is the recommended mixing time for glass ionomer cement? a. 10 to 20 seconds b. 20 to 30 seconds c. 30 to 60 seconds d. 2 minutes e. 7 minutes ANS: C

A B C D E

Feedback This is 10 to 20 times shorter than recommended by the manufacturer. This is 20 to 30 times shorter than recommended by the manufacturer. The mixing time for glass ionomer should be 30 to 60 seconds. Two minutes is the maximum working time from the start of mixing. Seven minutes is the time it takes the material to set from the start of mixing.

DIF: Knowledge REF: p. 85 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 8. What is the purpose of cooling the glass mixing slab when mixing glass ionomer cement? a. Slow the setting reaction. b. Accelerate the setting reaction. c. Incorporate water into T thE eS mTixB. ANKSELLER.COM d. Allow more powder to be incorporated into the liquid. ANS: A

B C D

Feedback The purpose of cooling the glass mixing slab when mixing glass ionomer cement is to slow the setting reaction and to provide additional working time. The cement should not be used once a “skin” forms on the surface or when the consistency becomes noticeably thicker. Heat typically accelerates the setting reaction of a material. Glass ionomers are hydrophobic. More powder would be against manufacturers’ set limits.

DIF: Knowledge REF: p. 85 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 9. Which of the following statements is true of hybrid ionomer cements? a. They are oil-based cements. b. They are resin-modified zinc polycarboxylate cements. c. They may be used for cementation of zirconia-based all-ceramic crowns and

bridges. d. They are recommended for cementation of lower strength all-ceramic inlays,

onlays, or crowns. ANS: C

A B C D

Feedback Hybrid ionomers are water-based materials. Zinc polycarboxylate is not a glass ionomer. They may be used for cementation of zirconia-based all-ceramic crowns and bridges. They are water-based cements. They are not recommended for cementation of lower strength all-ceramic inlays and onlays because of their water sorption.

DIF: Knowledge REF: p. 87 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 10. The hybrid ionomer cement liquid should be dispensed by holding the vial

mixing pad. The cement is applied to a a. at an angle; dry b. at an angle; slightly moist c. vertically; dry d. vertically; slightly moiT s

to the

tooth.

ANS: C

A B C D

Feedback The bottle at an angle may not measure an accurate drop of liquid. Ionomers are hydrophobic materials, so dry application is necessary. The bottle at an angle may not measure an accurate drop of liquid. Ionomers are hydrophobic materials, so dry application is necessary. The hybrid ionomer cement liquid should be dispensed by holding the vial vertically to the mixing pad. The cement is applied to a dry tooth. The bottle at an angle may not measure an accurate drop of liquid. Ionomers are hydrophobic materials, so dry application is necessary.

DIF: Comprehension REF: p. 87 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 11. Which of the following statement(s) is/are true of zinc polycarboxylate cement? a. It is stronger than zinc phosphate cement. b. It is less irritating to the pulp than zinc phosphate cement. c. It is more irritating to the pulp than zinc phosphate cement.

d. A and B are both true. e. A and C are both true. ANS: B

A B C D E

Feedback Zinc phosphate cements are the stronger of the two materials. Zinc polycarboxylate cement is not as strong as zinc phosphate cement, but it is less irritating to the pulp. Zinc phosphate cements have a more irritating pH level and set by exothermic reaction. B is the only correct answer. B is the only correct answer.

DIF: Comprehension REF: p. 96 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 12. Which of the following statements is true of the manipulation of zinc polycarboxylate

cement? a. The proper consistency is creamy. b. The liquid is added to the powder. c. The mixing time is about 3 minutes. d. The cement should be m ixS edToBvAeN r aKlS arEgL eL arE eaRo.fCthOeMmixing surface. TE ANS: A

A B C D

Feedback The proper consistency of zinc polycarboxylate cement is creamy. The powder should be added to the liquid. Mixing time is 30 to 60 seconds depending on the product. The cement should be mixed over a small area of the mixing surface.

DIF: Knowledge REF: p. 96 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 13. The maximum working time for zinc polycarboxylate cement is a. 30 b. 60 c. 90 d. 120 ANS: D

seconds.

A B C D

Feedback Mixing time is 30 to 60 seconds. Mixing time is 30 to 60 seconds. A maximum of 90 seconds would not allow adequate working time. The maximum working time for zinc polycarboxylate cement is 3 minutes.

DIF: Knowledge REF: p. 96 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 14. Which of the following cements has a sedative effect on the pulp? a. Glass ionomer b. Zinc phosphate c. Calcium hydroxide d. Zinc oxide–eugenol e. Zinc polycarboxylate ANS: D

A B C D E

Feedback Glass ionomer cement releases a fluoride ion. Zinc phosphate cement is irritating. Calcium hydroxide stimulates development of reparative dentin. Zinc oxide–eugenol cT em haAs N aK seSdE atL ivLeEefRfe.cC t oOnMthe pulp. EeSnTt B Zinc polycarboxylate has minimal sedative properties.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 15. Which of the following cements is not water based? a. Glass ionomer b. Zinc phosphate c. Zinc oxide–eugenol d. Zinc polycarboxylate ANS: C

A B C D

Feedback Glass ionomer is water-based cement. Zinc phosphate is water-based cement. Zinc oxide–eugenol is oil based. Zinc polycarboxylate is water-based cement.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 16. Which solvent is useful for removal of set zinc oxide–eugenol cement? a. Ether b. Water c. Orange oil d. Turpentine e. Ethyl alcohol ANS: C

A B C D E

Feedback Ether is toxic if ingested. Water cleans up water-based cements. Orange oil is useful for removal of set zinc oxide–eugenol cement. Turpentine is toxic if ingested. Ethyl alcohol is toxic if ingested.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements TgESSuT MSC: NMDHE, 6.0 Providin ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.1 Properties and manipulation of materials 17. Which type of cement is composed of dimethacrylate resin and glass filler? a. Zinc polycarboxylate b. Zinc oxide–eugenol c. Zinc phosphate d. Glass ionomer e. Esthetic resin ANS: E

A B C D E

Feedback Zinc polycarboxylate is zinc based, nonesthetic material. Zinc oxide–eugenol is zinc based, nonesthetic material. Zinc phosphate is zinc based, nonesthetic material. Glass ionomers are composed of aluminosilicate glass. Esthetic resin cement is composed of dimethacrylate resin and glass filler.

materials 18. Compomer cement is indicated for cementation of which of the following types of

restorations? a. Ceramic–metal crowns b. Traditional all-ceramic inlays c. Traditional all-ceramic crowns d. A, B, and C e. A and C ANS: A

A B C D E

Feedback Compomer cement is indicated for cementation of ceramic–metal crowns and cast alloy restorations. Cementation of traditional all-ceramic crowns, inlays, onlays, and veneers is contraindicated. Cementation of traditional all-ceramic crowns, inlays, onlays, and veneers is contraindicated. A is the only correct answer. A is the only correct answer.

DIF: Comprehension REF: p. 97 OBJ: 17 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.1 Properties and manipulation of TESSupp TBorAtiN materials 19. Which of the following high-strength bases has the highest modulus of elasticity? a. Glass ionomer b. Zinc phosphate c. Zinc polycarboxylate d. Resin-modified glass ionomer ANS: B

A B C D

Feedback Glass ionomer has a significantly lower modulus of elasticity. Zinc phosphate has the highest modulus of elasticity, meaning it is stiffest. Zinc polycarboxylate has a significantly lower modulus of elasticity. Resin-modified glass ionomer has a significantly lower modulus of elasticity.

mm thick.

a. 0.05 b. 0.5 c. 1.5 d. 5 ANS: B

A B C D

Feedback 0.05 mm is too thin. Effective thermal protection requires that a base be at least 0.5 mm thick. 1.5 mm is too thick and may not allow adequate room for a restoration. 5 mm is too thick and may not allow adequate room for a restoration.

DIF: Knowledge REF: p. 91 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 21. Which materials may be used as a base for composites but not with traditional ceramics? a. Compomer b. Zinc phosphate c. Hybrid ionomer d. A, B, and C e. A and C ANS: E

A B C D E

Feedback A and C are correct answers. Zinc phosphate cement would not be used as a base for composites. A and C are correct answers. A and C are correct answers. Compomer and hybrid ionomer may all be used as a base for composites but are not used with traditional ceramics.

DIF: Comprehension REF: p. 91 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 22. Which of the following materials used as bases is supplied as a single-paste compule that does

not require mixing? a. Compomer b. Glass ionomer c. Zinc phosphate d. Hybrid ionomer e. Zinc polycarboxylate

ANS: A

A B C D E

Feedback Compomer is supplied as a single-paste compule that does not require mixing. Glass ionomer has two component materials that must be mixed. Zinc phosphate has two component materials that must be mixed. Hybrid ionomer has two component materials that must be mixed. Zinc polycarboxylate has two component materials that must be mixed.

DIF: Knowledge REF: p. 92 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 23. Which of the following cements exhibits and exothermic reaction? a. Compomer b. Glass ionomer c. Zinc phosphate d. Zinc oxide–eugenol e. Zinc polycarboxylate ANS: C

A B C D E

Feedback TaEteSrT Compomer is a base m iaB l. ANKSELLER.COM Glass ionomer is used to permanently cement indirect restorations. Zinc phosphate is acidic and gives off heat as it sets. Zinc oxide–eugenol cement is the cement used most frequently as a temporary filling. Zinc polycarboxylate is used to permanently cement indirect restorations.

DIF: Knowledge REF: p. 96 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 24. Which of the following cements is used for pulp capping? a. Zinc polycarboxylate b. Zinc oxide–eugenol c. Calcium hydroxide d. Zinc phosphate e. Glass ionomer ANS: C

Feedback

A B C D E

Zinc polycarboxylate is used as a high-strength base. Zinc oxide–eugenol is used as a high-strength base. Calcium hydroxide cement is used for direct and indirect pulp capping. It is a low-strength base that stimulates formation of reparative dentin. Zinc phosphate cement is irritating to the pulp. Glass ionomer is used as a high-strength base.

dentin? a. Zinc phosphate b. Hybrid ionomer c. Calcium hydroxide d. Zinc oxide–eugenol e. Zinc polycarboxylate ANS: C

A B C D E

Feedback Zinc phosphate cement is irritating to the pulp. Hybrid ionomer is useTdEaS sT aB hiA ghN-K stS reE ngLtL hE baRse..COM Calcium hydroxide is used to stimulate the formation of reparative dentin. Zinc oxide–eugenol is used as a high-strength base. Zinc polycarboxylate is used as a high-strength base.

DIF: Knowledge REF: p. 92 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 26. Why are varnishes and cavity liners used prior to placing a direct restoration? a. Function as a protective barrier between dentin and the restorative material b. Minimize the ingress of oral fluids at the restoration–tooth interface c. Protect the pulp from the high pH of calcium hydroxide d. A, B, and C are correct. e. Only A and B are correct. ANS: E

A B

Feedback Both A and C are correct answers. Calcium hydroxide is a liner material.

C D E

Both A and C are correct answers. Only A and C are correct answers. Cavity liners and varnishes function as a protective barrier between dentin and the restorative material and minimize the ingress of oral fluids at the restoration–tooth interface. They are not used, however, to protect the pulp from the high pH of calcium hydroxide. Calcium hydroxide is applied directly to the tooth to stimulate formation of reparative dentin.

DIF: Comprehension REF: p. 92 OBJ: 13 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials, 6.2 Polishing natural and restored teeth 27. Why are varnishes used? a. Reduce leakage around margins and walls of the restoration–tooth interface b. Insulate the pulp from deep or large restorations c. Stimulate the formation of reparative dentin d. Function as a therapeutic base ANS: A

A B C D

Feedback Cavity varnishes are applied in order to reduce leakage around margins and walls of the restoration–tooth interface. High-strength bases inTsE ulSatTeBpA ulN p.KSELLER.COM Calcium hydroxide stimulates reparative dentin formation. Cavity varnishes do not provide a sedative effect.

DIF: Knowledge REF: p. 93 OBJ: 13 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 28. Direct and indirect bonding of orthodontic brackets is accomplished primarily with the use of a. b. c. d. e.

cements. calcium hydroxide zinc phosphate glass ionomer compomer resin

ANS: E A B C

Feedback Calcium hydroxide is used as a low-strength base/liner. Zinc phosphate is acidic. Glass ionomer is used as a base.

D E

Compomer is used as a base. Direct and indirect bonding of orthodontic brackets is accomplished primarily with the use of resin cements.

DIF: Knowledge REF: p. 93 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 29. Orthodontic bands may be cemented with which of the following cement(s)? a. Glass ionomer b. Zinc phosphate c. Zinc oxide–eugenol d. A and B e. B and C ANS: D

A B C D E

Feedback Both A and B are correct answers. Zinc phosphate is acidic but occasionally used to cement orthodontic bands. Zinc oxide–eugenol cements are used for sedative bases. Orthodontic bands may be cemented with glass ionomer or zinc phosphate cement. Both A and B are corrTeE ctSaT nsBwAeN rsK ;C isLinLcE orRre.cC t. OM SE

DIF: Comprehension REF: p. 93 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 30. What is the main function of dental cements? a. Insulate the pulp. b. Reinforce missing tooth structure. c. Retain restorations on prepared teeth. d. Initiate formation of reparative dentin. ANS: A

A B C D

Feedback This is a purpose of cements but is not as significant as retention of restorations. This is a purpose of cements but is not as significant as retention of restorations. The retention of restorations on prepared teeth is a major function of dental cements. This is a purpose of cements but is not as significant as retention of restorations.

DIF: Knowledge

REF: p. 85

OBJ: 1

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 31. Which of the following is not a water-based cement? a. Glass ionomer b. Hybrid ionomer c. Zinc oxide–eugenol d. Zinc polycarboxylate ANS: C

A B C

Feedback Glass ionomer is a water-based cement. Hybrid ionomer is a water-based cement.. Zinc oxide–eugenol cements are oil-based cements that have an obtundent (sedative) effect on the pulp and are especially useful for cementation on prepared teeth with exposed dentinal tubules. Zinc polycarboxylate is a water-based cement.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 32. When are hybrid ionomer cements used? a. To cement all-ceramic restorations b. To cement core buildups c. To bond orthodontic appliances d. All of the above ANS: D

A B C D

Feedback A, B, and C are all correct answers. A, B, and C are all correct answers. A, B, and C are all correct answers. Hybrid ionomer cements are used to cement core buildups, all-ceramic restorations, and orthodontic appliances.

33. Which cement is closest to glass ionomer in compressive and tensile strength? a. Zinc polycarboxylate b. Zinc oxide–eugenol c. Hybrid ionomer d. Adhesive resin ANS: C

A B C D

Feedback Zinc polycarboxylate is lower in tensile strength. Zinc oxide–eugenol is lower in tensile strength. The values for compressive and tensile strengths of hybrid ionomer cements are similar to those of glass ionomer cements. Adhesive resin has a higher tensile strength.

DIF: Comprehension REF: p. 87 OBJ: 2 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 34. Properties of zinc polycarboxylate cement include which of the following? a. Moderate strength b. High viscosity c. Mild acidity d. All of the above e. Only A and C ANS: E

A B C D E

Feedback A and C are both correct. Zinc polycarboxylate cement has a moderate viscosity. Too high of a viscosity may not allow the restoration to seat properly. A and C are both correct. Only A and C are correct. The important properties of zinc polycarboxylate cements are moderate viscosity, moderate strength, ability to bond to enamel, and mild acidity.

DIF: Comprehension REF: p. 96 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 35. Which cement shows histologic reactions similar to zinc polycarboxylate cement? a. Resin-modified ionomer b. Zinc oxide–eugenol c. Glass ionomer

d. Zinc phosphate ANS: B

A B C D

Feedback Resin-modified ionomer can be used as a base. Histologic reactions are similar to those of zinc oxide–eugenol cements, but more reparative dentin is observed with the polycarboxylates. Glass ionomer can be used as a base. Zinc phosphate is too acidic.

DIF: Knowledge REF: p. 97 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 36. When are esthetic resin cements used? a. Fill root canals b. Bond metal restorations c. Bond ceramic restorations d. Bond orthodontic brackets ANS: C

A B C

Feedback Root canal cements arTeEuS suTaB llyAzNinKcSoExL idL e–EeR ug.eC noOlMbased. Zinc polycarboxylate would be a better choice to cement a metal restoration since esthetics is not an issue. Esthetic resin cements are tooth-colored or translucent resins available in a variety of shades and are used for bonding of all-ceramic and indirect composite restorations. Orthodontic brackets are cemented with resin cements. Again, esthetics is not an issue.

DIF: Knowledge REF: p. 88 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 37. Why is rosin, 29%, added to Type I zinc oxide–eugenol cement powder? a. Reduce brittleness b. Act as a sedative c. Accelerate set d. A and C are correct. ANS: A

A B C D

Feedback The zinc oxide–eugenol cement powder (Type I) contains zinc oxide (69%) with rosin (29%) to reduce brittleness. Zinc and eugenol add sedative properties. Accelerators are added to assist with set. A is the only correct answer.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 38. Zinc oxide–eugenol cement is a single paste system. Zinc oxide–eugenol cements should be

mixed with a plastic spatula. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is incorrect; statement 2 is correct. c. Statement 1 is correct; statement 2 is incorrect. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

A B C D

Feedback Both statements are incorrect. Both statements are incorrect. Both statements are inTcE orSreTcB t. ANKSELLER.COM The permanent zinc oxide–eugenol cements (Type II) are powder–liquid systems. They are mixed on a glass slab or treated paper pad with a metal spatula.

DIF: Comprehension REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 39. When would an adhesive resin cement not be used? a. Indirect esthetic restoration b. Metal ceramic crown c. Alloys d. All of the above e. A and B only ANS: A

Feedback Adhesive resin cements are used for bonding of most alloy and ceramic restorations, except veneers, implant-supported crowns and bridges, and indirect esthetic restorations.

B C D E

Adhesive resin can be used with this type of restoration. Adhesive resin can be used with this type of restoration. A is the only correct answer. A is the only correct answer.

DIF: Comprehension REF: p. 89 OBJ: 6 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 40. Self-adhesive resin cements eliminate the need for primer and bond. They are as strong as

adhesive resin cements. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is incorrect; statement 2 is correct. c. Statement 1 is correct; statement 2 is incorrect. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C

Feedback Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect. Self-adhesive resin cements bond to tooth structure and other materials with low to medium bond strengths. They generally are not as strong as esthetic and adhesive resin cementTs.ESTBANKSELLER.COM Statement 1 is correct; statement 2 is incorrect.

DIF: Comprehension REF: p. 90 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 41. Which cement can be mixed to a luting consistency or to a ball consistency? a. Zinc phosphate b. Glass ionomer c. Calcium hydroxide d. Zinc oxide–eugenol ANS: A

Feedback Zinc phosphate cement can be used as a ball stage (base), but due to its acidic content and exothermic reaction, it may cause pulpal irritation. It can also be mixed to a luting consistency to cement indirect restorations. Glass iononomer cement is used to cement indirect restorations and orthodontic bands or as filling material for Cl V restoration when the patient has a high caries rate.

C D

Calcium hydroxide is a liner material that promotes the formation of reparative dentin. Zinc oxide–eugenol cements are often used as a base for thermal insulation.

DIF: Knowledge REF: p. 90 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 42. Which of the following is correct regarding esthetic resin cements? a. Radiopaque b. Chemical cure c. Low bond strength d. High film thickness ANS: A

A B C D

Feedback Esthetic resin cements are radiopaque. Curing occurs using a visible light-curing unit. Esthetic resin cements have medium to high bond strength. Esthetic resin cements have a low film thickness.

DIF: Knowledge REF: p. 89 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 43. When is it recommended to use glass ionomer cements? a. Cavity liner b. Thermal base c. Cervical Cl V restorations d. Cement orthodontic bands ANS: C

A B C D

Feedback Cavity liners are suspensions of calcium hydroxide. Zinc oxide–eugenol cements are used as thermal bases. Resin-modified cements are used to cement orthodontic bands. Glass ionomers are used as Cl V restoration for patients with high caries rates.

DIF: Knowledge REF: p. 93 OBJ: 17 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) D, Other dental Materials, 1. Select and describe how to manipulate the various finishing, polishing, and cleaning agents MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of

materials 44. Which of the following is correct about root canal sealers? a. Zinc oxide–eugenol based b. Short working time c. High solubility d. Radiolucent ANS: A

A B C D

Feedback Most root canal sealers are zinc oxide–eugenol based. Longer working time in order to properly fill the canal Low solubility Radiopaque

DIF: Knowledge REF: p. 94 OBJ: 17 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 45. Which cement is used for provisional posterior restorations? a. Zinc phosphate b. Calcium hydroxide c. Zinc oxide–eugenol d. Zinc polycarboxylate ANS: C

A B C D

Feedback Zinc phosphate cement is used as a luting cement or as a high-strength base. Calcium hydroxide is a liner that promotes the formation of reparative dentin. Zinc oxide–eugenol can be used as a provisional restoration due to its sedative properties. Water-based cement is used for retention of crowns and bridges.

DIF: Knowledge REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials SHORT ANSWER 1. Explain how water-based cements differ from oil-based cements. ANS:

Glass ionomer cements are the most common of the water-based cements. Glass ionomers are used for cementing indirect restorations and cementing orthodontic bands and as restorations along the cervix of the tooth for patients with a high caries rate. Oil-based cements and zinc oxide–eugenol cements are oil-based cements that have an obtundent (sedative) effect on the pulp and are especially useful for cementation on prepared teeth with exposed dentinal tubules. The addition of reinforcing agents to zinc oxide–eugenol cement has resulted in permanent luting cements. Temporary cements are not so strong but are useful for short-term cementation of temporary stainless steel crowns and permanent restorations. Zinc oxide–non-eugenol cements are cements used for short-term cementation of temporary acrylic crowns and completed cast restorations. They are weak and easily cleaned from the casting. DIF: Comprehension REF: p. 88 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials 2. Compare and contrast high-strength bases, liners, and varnishes. ANS:

High-strength bases are used when there is sufficient tooth structure missing and a tooth requires a thermal base for protection. Cements such as zinc oxide–eugenol cements are preferred due to their sedative qualities and can also be used as provisional restorations. Liners such as calcium hydroxide are used when there is insufficient dentin remaining between the preparation anTdEthSeTpB ulApNcK haSmEbL erL. E CR al. ciC um OMhydroxide helps to stimulate reparative dentin. Varnishes such as copal are used under some restorations to seal dentinal tubules and help prevent microleakage. DIF: Comprehension REF: p. 90 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to g. varnishes, bases, and liners MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.1 Properties and manipulation of materials

Chapter 08: Impression Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. The impression gives a _

reproduction of tissue. A reproduction is obtained by pouring dental stone or other suitable material into the impression and allowing it to harden. a. negative; negative b. positive; positive c. negative; positive d. positive; negative ANS: C

Feedback The impression gives a negative reproduction of tissue. A positive reproduction is obtained by pouring dental stone or other suitable material into the impression and allowing it to harden. The impression gives a negative reproduction of tissue. A positive reproduction is obtained by pouring dental stone or other suitable material into the impression and allowing it to harden. The impression gives a negative reproduction of tissue. A positive reproduction is obtained by pouring dental stone or other suitable material into the impression and allowing it to harden. The impression givesTaEnS egTaB tivAeNrK epSroEdL uL ctE ioR n. ofCtO isM sue. A positive reproduction is obtained by pouring dental stone or other suitable material into the impression and allowing it to harden.

DIF: Comprehension REF: p. 98 OBJ: 1 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 2. Which of the following is a rigid dental impression material? a. Polyether b. Polysulfide c. Addition silicone d. Zinc oxide–eugenol ANS: D

A B C D

Feedback Polyether is a flexible material. Polysulfide is a flexible material. Addition silicone is a flexible material. Zinc oxide–eugenol is a rigid dental impression material.

DIF: Knowledge REF: p. 100 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 3. Which type of impression material is the most popular for restorative procedures? a. Polyether b. Polysulfide c. Hydrocolloid d. Addition silicone ANS: D

A B C D

Feedback Polyether materials have high dimensional change and are not accurate for restorative procedures. Polysulfide materials have high dimensional change and are not accurate for restorative procedures. Hydrocolloids do not show enough definition for restorative procedures. Addition silicone (51%) is the most popular for restorative procedures.

DIF: Knowledge REF: p. 106 OBJ: 13 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 4. What is the main disadvantage of alginate hydrocolloid impression material in contrast to an

elastomeric impression? a. Its higher cost b. The amount of equipment necessary c. The inflexibility of the set impression d. Difficulty in mixing and manipulating e. It does not transfer as much surface detail to gypsum dies. ANS: E

A B C D E

Feedback Alginate is inexpensive. Alginate does not require a lot of equipment. Alginate is flexible. Alginate does not require expensive equipment to mix and is easy to mix and manipulate. Alginate hydrocolloid impression material does not transfer as much surface detail to gypsum dies as elastomeric impression material.

DIF: Knowledge

REF: p. 100

OBJ: 3

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 5. When is alginate hydrocolloid recommended? a. Preparation of study models b. Impressions of cavity preparations c. In the preparation of athletic mouth protectors d. For A, B, and C e. For A and C ANS: E

A B C D E

Feedback Both A and C are correct answers. It is not recommended for impressions of cavity preparations. Both A and C are correct answers. Only A and C are correct answers. Alginate hydrocolloid is recommended for preparation of study models and in the preparation of athletic mouth protectors.

DIF: Comprehension REF: p. 100 OBJ: 3 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 6. How is alginate hydrocolloid supplied? a. Powder b. Compules c. Thixotropic gel d. Two syringes to be mixed together e. Two tubs as a putty system for hand kneading ANS: A

A B C D E

Feedback Alginate is supplied as a powder. Alginate is supplied as a powder. A thixotropic gel is used to deliver topical fluoride. Syringes are dispensing mechanisms for elastomeric materials. Tubs are dispensing mechanisms for elastomeric materials.

DIF: Knowledge REF: p. 100 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and

preparations for study casts 7. Which of the following ingredients of alginate hydrocolloid reacts with dissolved alginate to

form insoluble calcium alginate? a. Calcium sulfate b. Potassium sulfate c. Sodium phosphate d. Sodium or potassium alginate salt ANS: A

A B C D

Feedback Calcium sulfate reacts with dissolved alginate to form insoluble calcium alginate. Potassium sulfate counteracts inhibiting effects. Sodium phosphate is a retarder. Sodium or potassium alginate salt dissolves in water.

DIF: Knowledge REF: p. 102 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 8. Sodium phosphate acts as T a(E n)STBANKSdEuL riL ngEtR he.sCeO ttiMng reaction of alginate hydrocolloid. a. initiator b. retarder c. sweetener d. accelerator e. disinfectant ANS: B

A B C D E

Feedback Setting reaction is initiated when water is added to the powder. Sodium phosphate acts as a retarder during the setting reaction of alginate hydrocolloid. Phenylalanine is added as a sweetener. Setting time can be altered by adjusting the temperature of the water. Quaternary ammonia or chlorhexidine provides self-disinfection.

DIF: Knowledge REF: p. 102 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 9. Alginate impression material may be referred to as which type of material?

a. b. c. d. e.

Polyether Addition silicone Condensation silicone Irreversible hydrocolloid Reversible hydrocolloid

ANS: D

A B C D E

Feedback Polyether is an elastomeric material. Addition silicone is an elastomeric material. Condensation silicone is an elastomeric material. Alginate impression material may be referred to as an irreversible hydrocolloid. Reversible hydrocolloids are moderated by temperature changes.

DIF: Knowledge REF: p. 102 OBJ: 4 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 10. What is the recommended mixing time of fast-setting alginate? a. Less than 15 seconds b. 30 to 45 seconds c. 1.25 minutes d. 2 minutes ANS: B

A B C D

Feedback This is insufficient time to incorporate all material to a homogeneous consistency. The mixing time of fast-setting alginate is 30 to 45 seconds. This is the workable time for fast-setting alginate. This is the workable time for regular-setting alginate.

DIF: Knowledge REF: p. 102 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 11. The ANSI-ADA specification requires no more than

alginate is compressed 20% for 5 seconds. a. 2 b. 5 c. 25 d. 50 e. 95

% permanent deformation when an

ANS: B

A B C D E

Feedback Many commercial alginates have actual permanent deformation rates of 2% to 4%. The ANSI-ADA specification requires no more than 5% permanent deformation when an alginate is compressed 20% for 5 seconds. This is an unacceptable rate for deformation. This is an unacceptable rate for deformation. This is the amount of elastic recovery required.

DIF: Comprehension REF: p. 102 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 12. What is the ANSI-ADA requirement for recovery of alginate impression materials? a. 80% b. 85% c. 90% d. 95% ANS: D

A B C D

Feedback This is not an acceptable recovery rate. This is not an acceptable recovery rate. This is not an acceptable recovery rate. ANSI-ADA requires that alginate impression materials must recover at a rate of 95%.

DIF: Knowledge REF: p. 102 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 13. Higher rates of alginate deformation result in higher compressive and tear strengths. Alginate

impressions are more likely to tear during removal from the mouth when they are removed rapidly. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

Feedback Higher rates of alginate deformation result in higher compressive and tear strengths; thus alginate impressions are less likely to tear during removal from the mouth when they are removed rapidly. Higher rates of alginate deformation result in higher compressive and tear strengths; thus alginate impressions are less likely to tear during removal from the mouth when they are removed rapidly. Higher rates of alginate deformation result in higher compressive and tear strengths; thus alginate impressions are less likely to tear during removal from the mouth when they are removed rapidly. Higher rates of alginate deformation result in higher compressive and tear strengths; thus alginate impressions are less likely to tear during removal from the mouth when they are removed rapidly.

DIF: Comprehension REF: p. 103 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 14. Storing set alginate will result in the least dimensional change. a. in dry air b. under water c. in air approaching 50% relative humidity d. in air approaching 100% relative humidity ANS: D

A B C D

Feedback Alginates dry out if not kept moist. If the alginate is stored under water it will absorb additional water and deform. This is enough moisture to prevent syneresis. Storing set alginate in air approaching 100% relative humidity will result in the least dimensional change.

DIF: Comprehension REF: p. 103 OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 15. Which term describes the process through which alginate gels shrink and lose water? a. Syneresis b. Imbibition c. Dehydration d. Agglutination e. Agglomeration ANS: A

A B C D E

Feedback With time, alginate gels shrink and lose water through a process called syneresis. Imbibition is the act of absorbing water. Dehydration involves loss of water through evaporation. Agglutination means to glue. Agglomeration is the bringing together of a mass.

DIF: Knowledge REF: p. 104 OBJ: 12 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) B, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to b. cements MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 16. Alginate impressions prepared from extended storage products usually can be stored under

proper conditions for up to a. 10 minutes b. 1 hour c. 1 day d. 5 days e. 2 weeks

without serious dimensional changes.

ANS: D

A B C D

Feedback This is within acceptaT blEeSwToB rkAinNgKtiS mEeL . LER.COM Syneresis begins if less than ideal conditions occur. Significant syneresis occurs including significant dimensional change in less than ideal conditions. Alginate impressions prepared from extended storage products usually can be stored under proper conditions for up to 5 days without serious dimensional changes. Alginate would deform and be unusable even under ideal conditions.

DIF: Knowledge REF: p. 104 OBJ: 12 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 17. Measurement of dimensional changes showed that immersion of alginate impressions for a. b. c. d. e.

did not affect their clinical accuracy. 10 minutes 30 minutes 1 hour 5 days 2 weeks

ANS: B

A B C D E

Feedback Ten minutes is an insignificant time frame. Measurement of dimensional changes showed that immersion of alginate impressions for 30 minutes did not affect their clinical accuracy. One hour would result in significant distortion. Five days would result in significant distortion. Two weeks would result in significant distortion.

DIF: Knowledge REF: p. 104 OBJ: 12 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 18. What are the recommendations for mixing alginate? a. Using ice water b. Adding the powder to the water c. Adding the water to the powder d. Both A and B e. Both A and C ANS: B

A B C D E

Feedback The water should be aTt E roSoT mBteAmNpKeS raE tuL reL. ER.COM Adding the powder to the water is recommended. Adding the water to the powder may keep the powder from incorporating completely. B is the correct answer. B is the correct answer.

DIF: Knowledge REF: p. 102 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 19. At final seating, the incisal edges and cuspal tips should be a. contacting b. about 1 to 2 mm from c. about 3 to 4 mm from d. at least 6 mm from ANS: B

Feedback Contacting the tray could skew the accuracy of the impression.

the surface of the tray.

B C D

At final seating, the incisal edges and cuspal tips should be about 1 to 2 mm from the surface of the tray. If the tray is not seated properly, then other areas of the impression, mucobuccal fold and frenum, may not be accurately represented. If the tray is not seated properly, then other areas of the impression, mucobuccal fold and frenum, may not be accurately represented.

DIF: Comprehension REF: p. 105 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 20. What is the best method for delaying the setting of alginate? a. Increase the water temperature. b. Reduce the water temperature. c. Use a thinner mix of alginate. d. Use a thicker mix of alginate. ANS: B

A B C D

Feedback Increasing the water temperature would accelerate the setting of the alginate. The best method for delaying the setting of alginate is to reduce the water temperature. Using a thinner mix oT fE alS giT naBteAw illSrE esL ulLt E inRlo.w tear strength. NK CeOr M Using a thicker mix would produce less detail.

DIF: Knowledge REF: p. 106 OBJ: 11 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 21. What is an advantage of using an elastomeric impression material over an irreversible

hydrocolloid? a. Less expensive b. Reversible process c. Greater dimensional accuracy d. Best material for study models ANS: C

A B C

Feedback Elastomeric materials are more expensive. Elastomeric materials are irreversible. Except for the preparation of study models, elastomeric impression materials dominate the market mainly as a result of their greater accuracy, dimensional stability with time, and ability to record detail as compared with the hydrocolloid

materials. Alginate is the accepted material for study models.

DIF: Knowledge REF: p. 106 OBJ: 13 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 22. Bubbles are produced in gypsum dies if poured within which time period? a. Less than 1 hour b. 1 hour c. More than 1 hour d. None of the above; bubbles are not an issue ANS: A

A B C D

Feedback The hydrogen is released gradually from the set impression material and produces bubbles in gypsum dies poured in less than 1 hour. Hydrogen bubbles are not an issue after 1 hour. Hydrogen bubbles are not an issue after 1 hour. Hydrogen bubbles are not an issue after 1 hour.

DIF: Knowledge REF: p. 107 OBJ: 17 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 23. Which of the following is not true about alginate substitute materials? a. Higher dimensional stability b. Greater accuracy c. Better recovery d. Lower cost ANS: D

A B C D

Feedback This answer is correct. This answer is correct. This answer is correct. Addition silicones are more expensive than alginate.

preparations for study casts 24. Which of the following are correct regarding silicone putties? a. May be mixed with bare hands b. Should not be mixed with bare hands c. Should not be mixed when latex rubber gloves are worn d. A and C e. B and C ANS: D

A B C D E

Feedback Addition silicone may be mixed with bare hands. B and C are both correct answers. B and C are both correct answers. A is incorrect; B and C are both correct. Vinyl gloves and bare hands are acceptable. Addition silicone should not be mixed when latex rubber gloves are worn, because components in the latex rubber will retard or prevent the setting by poisoning the platinum catalyst.

DIF: Knowledge REF: p. 109 OBJ: 18 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts

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25. Which of the following factors limit the accuracy of wax bite registrations? a. Distortion on removal b. Release of internal stress on storage c. Minimal dimensional changes from mouth to room temperature d. A, B, and C e. A and B ANS: E

A B C D E

Feedback A and B are correct. A and B are correct. There are large amounts of dimensional change from mouth to room temperature. Only A and B are correct Distortion on removal, release of internal stress on storage, and large dimensional changes from mouth to room temperature all limit the accuracy of wax bite registrations.

DIF: Knowledge REF: p. 110 OBJ: 20 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and

preparations for study casts 26. Impression materials can be classified as those that are flexible and those that are rigid at the

time of removal from the mouth. A rigid impression material is restricted to applications in areas where undercuts exist. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B

C D

Feedback Statement 1 is correct; statement 2 is incorrect. Impression materials can be classified as those that are flexible and those that are rigid at the time of removal from the mouth. A rigid impression material is restricted to applications in areas where no undercuts exist. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect.

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27. What is/are the advantage(s) of using premeasured packets of alginate impression material? a. Impervious to moisture b. Less expensive than cans c. Premeasured for a full arch d. All of the above e. Only A and C ANS: E

A B C D E

Feedback A and C are both correct statements. Individual packages of material are more expensive than a bulk container. A and C are both correct statements. Only A and C are correct statements. The preweighed packages are constructed of plastic and metal foil and contain enough material for a single full-arch impression. These packages minimize moisture contact with the powder and extend the storage life of the alginate.

28. Alginates, when properly mixed by hand, should develop a

consistency free of in less than 1 minute for the normal set material and should be suitable for making impressions in the mouth. a. thixotropic; bubbles b. thixotropic; graininess c. smooth and creamy; bubbles d. smooth and creamy; graininess ANS: D

Feedback Alginates, when properly mixed by hand, should develop a smooth, creamy consistency free of graininess in less than 1 minute for the normal set material and should be suitable for making impressions in the mouth. Alginates, when properly mixed by hand, should develop a smooth, creamy consistency free of graininess in less than 1 minute for the normal set material and should be suitable for making impressions in the mouth. Alginates, when properly mixed by hand, should develop a smooth, creamy consistency free of graininess in less than 1 minute for the normal set material and should be suitable for making impressions in the mouth. Alginates, when properly mixed by hand, should develop a smooth, creamy consistency free of graininess in less than 1 minute for the normal set material and should be suitable for making impressions in the mouth.

DIF: Comprehension REF: p. 102 OBJ: 9 TOP: CDA, GC, III ChairsiT deEDSeT ntB alAMNaK teS riaElsL(L PrE epRa. raC tioOnM , Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 29. Of the following, which will alter setting times for alginates? a. Decreased water temperature b. Increased water temperature c. Decreased powder d. A, B, and C e. Only A and B ANS: D

A B C D

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. Because the setting occurs as a result of a chemical reaction, an increase in the temperature of the water used to prepare the mix shortens the working and setting times. The proportions of powder and water also affect the setting times. Thinner mixes increase the time required for the material to set. A, B, and C are all correct.

DIF: Knowledge REF: p. 102 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 30. The strength of alginate material a. increases; thinner b. increases; thicker c. decreases; thinner d. decreases; thicker e. Both B and D are correct. f. Both A and C are correct.

if a _

mixture is used.

ANS: E

A B C D E F

Feedback If too much water is added, the mixture will be thin and prone to tearing. B and D are both correct. If the mixture is thicker, the strength of the material increases. B and D are both correct. The strength of alginate impression materials is increased if thick rather than thin mixes are used. Strength will decrease if thinner mixes are used. B and D are the only correct answers.

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REF: p. 103 DIF: Comprehension OBJ: 5 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 31. If an alginate impression is left to soak in a wet environment, the material will expand by

which process? a. Syneresis b. Hysteresis c. Imbibition d. Dimensional change ANS: C

A B C D

Feedback Syneresis is the process in which water forms on the surface of the impression, causing the impression to shrink. Hysteresis is the retardation of effect. Imbibition is the taking in of water. Dimensional change is a result of the process.

DIF: Knowledge

REF: p. 104

OBJ: 12

TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 32. Which solutions are used to disinfect an impression? a. Alcohol b. Iodophor c. Sodium hypochlorite d. All of the above e. Only B and C ANS: E

A B C D E

Feedback Using alcohol could adversely affect the surface of the material. B and C are correct answers. B and C are correct answers. B and C are correct answers. Sodium hypochlorite, iodophor, glutaraldehyde, and phenylphenol solutions have been used, and some manufacturers have added disinfectants to the alginate powder.

DIF: Knowledge REF: p. 104 OBJ: 19 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 33. How should a maxillary impression tray fit? a. Leave a 2-mm border around the alveolar process b. Cover the distal of the most posterior tooth. c. Include the maxillary tuberosity. d. Extend past the mucobuccal fold. ANS: C

A B C D

Feedback The border should be 4 mm wider than the most apical portion of the alveolar process at the molar region. A proper fitting maxillary tray should cover the maxillary tuberosity. The tray should completely cover the tuberosity. If the flange extends too far, the patient’s tissue could be injured.

DIF: Knowledge REF: p. 104 OBJ: 7 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and

preparations for study casts 34. What is an accepted method for modifying an impression tray? a. Heating the tray to alter the configuration b. Applying rope wax to the flanges c. Adding compound to the edges d. None of the above ANS: B

A B C D

Feedback Heating a tray could undermine the stability needed to support the material. To be sure the alginate flows into the labial vestibule when the impression is seated, soft rope wax may be added to the anterior labial flange of the tray. The compound is hard and could be uncomfortable for the patient. Not all patients fit a tray size, so alteration is sometimes needed.

DIF: Knowledge REF: p. 105 OBJ: 8 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 35. Alginate should be mixed by adding powder to water. Alginate should be mixed with a

narrow, pliable spatula. a. Statement 1 is correct; statement 2 is correct. TB b. Statement 1 is correct; T stE atS em enAt N 2K isSinEcL orLreEcR t. .COM c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B C D

Feedback Statement 1 is correct; statement 2 is incorrect. With a stiff, wide-bladed spatula, the alginate powder is sifted into the water. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect.

DIF: Comprehension REF: p. 100 OBJ: 9 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 36. Early elastomeric impression materials include which of the following materials? a. Polyether b. Polyvinyl siloxane c. Condensation silicone d. All of the above

e. Only A and C ANS: E

A B C D E

Feedback A and C are correct. Polyvinyl siloxane is one of the newer, highly used, impression materials on the market today. Only A and C are correct. Only A and C are correct. The first elastomeric impression materials were polysulfides, followed by condensation silicones and polyethers.

DIF: Knowledge REF: p. 106 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 37. What is the dimensional change of addition silicone after 24 hours? a. −0.1% b. −1% c. 0.1% d. 1% ANS: A

B C D

Feedback Less dimensional change and higher elastic recovery are noteworthy improvements of the addition silicones over the earlier condensation silicones. The dimensional change in 24 hours of about −0.1% is very low. This exceeds the accepted limit. This exceeds the accepted limit. This exceeds the accepted limit.

DIF: Knowledge REF: p. 107 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 38. The dimensional change of polyethers is higher than that of the addition silicones. The

polyether absorbs water and changes dimensions if stored in contact with water until equilibrium is reached. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect.

ANS: A

B C D

Feedback The dimensional change of polyethers is higher than that of the addition silicones. The polyether absorbs water and changes dimensions if stored in contact with water until equilibrium is reached. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct.

DIF: Comprehension REF: p. 109 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 39. Why is it important to use vinyl gloves or bare hands to mix polyvinyl putty materials? a. Many patients are allergic to latex. b. Latex gloves retard the setting of the material. c. Latex gloves accelerate the setting of the material. d. A and C are correct. e. A and B are correct. ANS: B

A B C D E

Many patients are allergic to latex but this is not a factor when mixing putty. Latex gloves retard the setting of the material by poisoning the platinum catalyst. Latex gloves would interfere with the setting of this material. B is the correct answer. B is the correct answer.

DIF: Knowledge REF: p. 109 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 40. Which of the following is correct regarding addition silicone? a. Hydrophylic b. Hydrophobic c. High viscosity d. Low dimensional change ANS: A

A B

Feedback Polyethers are hydrophylic and wet easily. Polyethers are hydrophylic and wet easily.

C D

Polyethers have a low viscosity. The dimensional change of polyethers is higher than that of the addition silicones.

DIF: Knowledge REF: p. 109 OBJ: 16 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 41. Digital impressions are not as accurate as elastomeric impressions. CAD/CAM requires a

milling machine in order fabricate the indirect restoration. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is correct. Digital impressions are as accurate as elastomeric impressions if not more so. CAD/CAM utilizes a milling machine to fabricate the indirect restoration. Statement 1 is incorrect; statement 2 is correct.

DIF: Comprehension REF: p. 111 OBJ: 21 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts SHORT ANSWER 1. Compare and contrast alginate with elastomeric impression materials. ANS:

Alginate is one of the most widely used aqueous dental impression materials. The wide use of alginates results from (1) the ease of mixing and manipulating them, (2) the minimum equipment necessary, (3) the flexibility of the set impression, (4) their accuracy if properly handled, and (5) their low cost. Their principal disadvantages are that they have low tear strength and they do not transfer as much surface detail to gypsum dies as elastomeric impressions do. Elastomeric impression materials are flexible cross-linked polymers when set. Except for the preparation of study models, elastomeric impression materials dominate the market mainly as a result of their greater accuracy, dimensional stability with time, and ability to record detail as compared with the hydrocolloid materials.

DIF: Analysis REF: p. 107 OBJ: 12 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 2. Explain why an elastomeric bite registration might be preferable to a wax bite registration. ANS:

Bite registrations in the past have been taken in wax. The following factors limit the accuracy of wax bite registrations: (1) distortion on removal, (2) release of internal stress on storage, (3) high flow properties, and (4) large dimensional change from mouth to room temperature. Elastomeric bite registration materials ideally should (1) be fast setting, (2) be mousse-like in the tray, (3) have no taste or odor, (4) be rigid when set, and (5) be easy to trim. DIF: Knowledge REF: p. 110 OBJ: 20 TOP: CDA, GC, III Chairside Dental Materials (Preparation, Manipulation, and Application) A, 1, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to a. alginates, b. elastomerics MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts

Chapter 09: Model and Die Materials Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1.

are highly accurate replicas of a single tooth and generally are used to make metal crowns or inlays. a. Models b. Casts c. Dies d. A and C e. B and C ANS: C

A B C D E

Feedback Models are used for observation. Casts are used as working models. Dies are highly accurate replicas of a single tooth and generally are used to make metal crowns or inlays. C is the only correct answer. C is the only correct answer.

DIF: Comprehension REF: p. 118 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materialT s,E inSclT udBinAgNbK utSnE otLliL mE itR ed.tC oO 3,M c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 2. Gypsum model and die materials exhibit

in contrast to epoxy model and die materials. a. excellent compatibility with impression materials b. excellent abrasion resistance c. slight expansion d. both A and C e. both B and C ANS: D

A B C D

Feedback A and C are correct. Gypsum materials are easily abraded. A and C are correct. Gypsum materials exhibit excellent compatibility with impression materials and slight expansion in contrast to epoxy materials, which exhibit limited compatibility with impression materials and slight contraction upon setting. A and C are correct.

DIF: Comprehension

REF: p. 119

OBJ: 2

TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 3. Which of the following types of gypsum products is also known as die stone? a. Dental stone b. Model plaster c. Impression plaster d. High-strength/low-expansion dental stone e. High-strength/high-expansion dental stone ANS: D

A B C D E

Feedback Dental stone is used for casts that need abrasion resistance. Model plaster is used for casts that do not need abrasion resistance. Impression plaster is used to mount working models to an articulator. High-strength/low-expansion dental stone is also known as die stone. High-strength/high-expansion dental stone may not produce an accurate die.

ER 4. Orthodontic plaster is a miT xtE uS reToB fA wN haKt S twEoLcL om po.uC ndOsM ? a. Model plaster and dental stone b. Impression plaster and dental stone c. Impression plaster and model plaster d. High-strength/low-expansion and high-strength/high-expansion dental stone ANS: A

A B C D

Feedback Orthodontic plaster is a mixture of model plaster and dental stone. Dental stone is used for casts that need abrasion resistance. Impression plaster is used to mount working models to an articulator. High-strength/high-expansion dental stone may not produce an accurate die.

DIF: Knowledge REF: p. 120 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c, gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 5. Which of the following model and die materials are derived from the mineral gypsum? a. Dental stone b. Model plaster c. High-strength dental stone

d. A, B, and C e. A and C ANS: D

A B C D E

Feedback A, B, and C are correct answers. A, B, and C are correct answers. A, B, and C are correct answers. Model plaster, dental stone, and high-strength dental stone are all derived from the mineral gypsum. A, B, and C are correct answers.

DIF: Comprehension REF: p. 120 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 6. Which of the following statements is true of the production of dental stone? a. It is produced by heating gypsum in an open kettle. b. The hemihydrate produced is b-calcium sulfate hemihydrate. c. The hemihydrate produced is a-calcium sulfate hemihydrate. d. A and B are true statements. e. A and C are true statements. ANS: C

A B C D E

Feedback Plaster is produced by heating the gypsum in an open kettle. A hemihydrate produced is a porous powder called b-calcium sulfate hemihydrate. Dental stone is produced by heating gypsum under pressure in the presence of steam. The hemihydrate produced is a-calcium sulfate hemihydrate. C is the correct answer. C is the correct answer.

DIF: Knowledge REF: p. 120 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 7. Which of the following types of dental stones and dental plasters requires the least amount of

excess water? a. Dental stone b. Model plaster c. High-strength dental stone ANS: C

A B C

Feedback Dental stone requires higher amounts of water. Model plaster requires higher amounts of water. High-strength dental stone requires the least amount of excess water.

DIF: Knowledge REF: p. 120 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 8. Which form of dental gypsum product is created by boiling gypsum in a 30% solution of

calcium chloride? a. Dental stone b. Model plaster c. High-strength dental stone d. A and B e. B and C ANS: C

A B C D E

Feedback Dental stone is produced by heat under pressure. Model plaster is produced by heating the gypsum in an open kettle. High-strength dental stone is created by boiling gypsum in a 30% solution of calcium chloride. C is the only correct aTnE swSeTr.BANKSELLER.COM C is the only correct answer.

and to get a workable mass. a. larger; more b. larger; less c. smaller; more d. smaller; less

dense the crystal of the hemihydrate, the less excess water required

ANS: A

A B C D

Feedback The larger and denser the crystal of the hemihydrate, the less excess water required to get a workable mass. When the crystal is smaller or less dense, more water is required. When the crystal is smaller or less dense, more water is required. When the crystal is smaller or less dense, more water is required.

DIF: Comprehension REF: p. 120 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 10. Accelerators are chemicals that a. increase; increase b. increase; decrease c. decrease; increase d. decrease; decrease

the rate of setting and

the time of setting.

ANS: B

A B C D

Feedback Without accelerators, setting time increases, and the set rate decreases. Accelerators are chemicals that increase the rate of setting and decrease the time of setting. Without accelerators, setting time increases, and the set rate decreases. Without accelerators, setting time increases, and the set rate decreases.

DIF: Comprehension REF: p. 121 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 11. Which of the following chemicals is an effective accelerator for gypsum materials? a. Borax b. Calcium sulfate c. Potassium sulfate d. B-calcium sulfate hemihydrate e. A-calcium sulfate hemihydrate ANS: C

A B C D E

Feedback Borax extends the setting time. Calcium sulfate is a chemical found in model plaster. Potassium sulfate is an effective accelerator for gypsum materials. This is a type of gypsum. This is a type of gypsum.

DIF: Knowledge REF: p. 121 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 12. Which of the following materials will accelerate the setting reaction of gypsum products?

a. b. c. d. e.

Agar Blood Saliva Terra alba Unset alginate

ANS: D

A B C D E

Feedback Agar will retard the setting reaction of gypsum. Blood will retard the setting reaction of gypsum. Saliva will retard the setting reaction of gypsum. Terra alba will accelerate the setting reaction of gypsum products. Unset alginate will retard the setting reaction of gypsum.

DIF: Knowledge REF: p. 121 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 13. What occurs if an excessive amount of water is used to prepare gypsum materials? a. A reduction in the setting time b. Increased setting expansion c. A reduction in strength d. A, B, and C e. A and C ANS: B

A B C D E

Feedback There will be an increase in the setting time. It will result in a reduction in the setting expansion of set gypsum materials. Using excessive water to prepare gypsum materials will result in a reduction in strength. The only correct answer is B. The only correct answer is B.

DIF: Knowledge REF: p. 121 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 14. If the temperature of the water used to mix gypsum materials is raised up to body temperature

(37.5° C), the setting time decreases. However, if water temperature is raised above 37.5° C, the setting time will increase. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct.

d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Both statements are correct. Both statements are correct. Both statements are correct. Both statements are correct.

DIF: Comprehension REF: p. 122 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 15. What is a good way to determine the final setting time of gypsum material? a. Loss of surface gloss b. Dissipation of the heat of reaction c. When the material can no longer be poured d. When the conversion of hemihydrate to dihydrate is complete ANS: D

A B C D

Feedback A good way to determine the final setting time is dissipation of the heat of reaction. Re.iCs O A good way to determTinEeStT heBfA inNalKsS etEtiL ngLtE im diM ssipation of the heat of reaction. A good way to determine the final setting time is dissipation of the heat of reaction. A good way to determine the final setting time is dissipation of the heat of reaction.

DIF: Knowledge REF: p. 122 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 16. Which of the following statements is true of the compressive strengths of gypsum materials? a. Die stone has the lowest compressive strength, because it has the least excess

water. b. Die stone has the lowest compressive strength, because it has the most excess

water. c. Die stone is almost four times as strong in compression as plaster, because the

excess water is minimized. d. Die stone is almost four times as strong in compression as plaster, because the

excess water is maximized. ANS: C

A B C D

Feedback Plaster has the lowest compressive strength, because it has the most excess water. Plaster has the lowest compressive strength, because it has the most excess water. Die stone is almost four times as strong in compression as plaster, because the excess water is minimized. Die stone has minimal excess water.

its strength when dry. four times twice one-half one-quarter one-sixteenth

ANS: C

A B C D E

Feedback Four times is die stone’s compressive strength. This is too low and is an inaccurate strength. When a model or die is wet, its compressive and tensile strength is approximately one-half its strength when dry. This is too low and is an inaccurate strength. This is too low and is an inaccurate strength.

DIF: Knowledge REF: p. 124 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 18. For high-strength die materials, reproduction of detail is not critical because a precision

casting will be fabricated on the gypsum die. Reproduction of detail is measured by pouring the gypsum material against a metal die with lines of decreasing depth scribed on it. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is incorrect. d. Statement 1 is incorrect; statement 2 is correct. ANS: D

A B C D

Feedback Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is correct.

DIF: Comprehension REF: p. 123 OBJ: 9 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 19. How should gypsum powder and water be added to the mixing bowl? a. Water should be added first. b. Powder should be added first. c. The second material added should be sprinkled in slowly over a period of about 30

seconds. d. Both A and C e. Both B and C ANS: D

A B C D E

Feedback A and C are both correct. Powder is added to water in the mixing bowl in order to completely incorporate the powder and liquid. This is more difficult if the water is added to the powder. A and C are both corrT ecEt.STBANKSELLER.COM A and C are both correct. When powder and water are added to the mixing bowl, the water should be added first, and the second material (powder) should be sprinkled in slowly over a period of about 30 seconds.

DIF: Knowledge REF: p. 125 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 20. When gypsum is mixed by hand, the mass is stirred with a spatula at a rate of about

revolution(s) per second for a. five; about 5 minutes b. two; about 2 minutes c. two; about 1 minute d. one; about 2 minutes e. one; 30 seconds

ANS: C

Feedback The material would be harder to work with because of setting reactions if mixed

B C D E

for 5 minutes. There would be less working time if mixed for 2 minutes. When gypsum is mixed by hand, the mass is stirred with a spatula at a rate of about two revolutions per second for about 1 minute. There would be less working time if mixed for 2 minutes. The material would not be completely incorporated if mixed for 30 seconds.

DIF: Comprehension REF: p. 126 OBJ: 13 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 21. What is the purpose of the vibrating table? a. Helps remove any bubbles that formed during mixing b. Ensures a smooth mix of the materials c. Wets the gypsum powder particles d. Initiates the setting reaction ANS: B

A B C D

Feedback A smooth mix is achieved by efficient spatulation. The purpose of the vibrating table is to help remove any bubbles that formed during mixing. The powder is sifted into the liquid for 3 seconds to wet the powder particles. The setting process isTaEcS heTmBicAaN lK reS acEtiL onL.ER.COM

DIF: Knowledge REF: p. 123 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 22. The impression should not be removed from the gypsum for a. 3 to 5 b. 5 to 10 c. 10 to 20 d. 20 to 40 e. 45 to 60

minutes.

ANS: E

A B C D E

Feedback Early removal often fractures the model. Early removal often fractures the model. Early removal often fractures the model. Early removal often fractures the model. The impression should not be removed from the gypsum for 45 to 60 minutes.

DIF: Knowledge REF: p. 122 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 23. What happens if alginate dries out before the gypsum is poured? a. The alginate will rob the gypsum mix of some of its water. b. The edges of the alginate may tear off. c. The impression will be distorted. d. A, B, and C are correct. e. A and C are correct. ANS: E

A B C D E

Feedback A and C are correct. The edges of alginate become hard and inflexible. A and C are correct. A and C are correct. When the alginate dries out before it is poured, the alginate will rob the gypsum mix of some of its water; the edges of the alginate may become hard and inflexible; and the impression will be distorted.

DIF: Comprehension REF: p. 127 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 24. Which of the following statements is true of the handling of an alginate impression? a. The heat produced is the result of an endothermic reaction. b. Any residual water in low places of the impression should not be removed. c. The poured impression may be kept moist by storing it in a humid environment. d. An alginate impression should be rinsed completely and disinfected after pouring. ANS: C

A B C D

Feedback The heat produced is the result of an exothermic reaction. Any residual water in low places of the impression should be removed. The poured impression may be kept moist by storing it in a humid environment. An alginate impression should be rinsed completely and disinfected before pouring. Water left in the impression could leave voids in the anatomic portion of the model.

DIF: Knowledge REF: p. 127 OBJ: 13 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts

25. Which of the following statements is true regarding disinfection of a gypsum model? a. The model may be sterilized in an autoclave. b. Disinfecting the impression rather than the model is preferable. c. Disinfecting the model rather than the impression is preferable. d. A and B are true statements. e. A and C are true statements. ANS: B

A B C D E

Feedback The model may not be sterilized in an autoclave; however, a gypsum model can be sterilized in ethylene oxide. Disinfecting the impression rather than the model is preferable. Not all disinfectants are compatible with gypsum products. B is the only correct answer. B is the only correct answer.

DIF: Comprehension REF: p. 128 OBJ: 14 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 26. What are gypsum casts used for? a. Inlays b. Crowns c. Retainers d. All of the above ANS: C

A B C D

Feedback Dies are highly accurate replicas of a single tooth and generally are used to make metal crowns or inlays. Dies are highly accurate replicas of a single tooth and generally are used to make metal crowns or inlays. Casts of teeth are used to make orthodontic retainers, and casts of the remaining ridges in the edentulous patient are used to make dentures for the patient. C is the only correct answer.

DIF: Knowledge REF: p. 118 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 27. Which statement(s) is (are) correct about making models, casts, and dies? a. Fine detail is not significant. b. Gypsums are not dimensionally stable. c. The material does not need to be strong.

d. A, B, and C are all correct. e. A, B, and C are all incorrect. ANS: E

A B C D E

Feedback When making models, casts, and dies, reproduction of fine detail is important. When making models, casts, and dies, dimensional stability is important. When making models, casts, and dies, the material does need to be strong. All of the answers are incorrect. A number of qualities are required of materials to be used for making models, casts, or dies. These qualities are accuracy, dimensional stability, reproduction of fine detail, strength and resistance to abrasion, and ease of adaptation to the impression, color, and safety, among others.

materials can be used with alginates. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrecT t;EstSatTem enNt K 2S isEinLcLoE rreRc. t.COM BA ANS: B

A B C D

Feedback Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect.

DIF: Comprehension REF: p. 128 OBJ: 16 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 29. Why do high-strength stone crystals require the least amount of excess water? a. Large and dense b. Large and sparse c. Small and dense d. Small and sparse ANS: A

Feedback

A B

High-strength stone, with its large, dense crystals, requires the least excess water. Dental stone requires somewhat more water, and plaster requires the most excess water. In general the larger and denser the crystal size of the hemihydrate, the less excess water required to get a workable mass. Dental stone requires somewhat more water, and plaster requires the most excess water. In general the larger and denser the crystal size of the hemihydrate, the less excess water required to get a workable mass. Dental stone requires somewhat more water, and plaster requires the most excess water. In general the larger and denser the crystal size of the hemihydrate, the less excess water required to get a workable mass.

DIF: Knowledge REF: p. 120 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 30. If a 2% solution of borax is added to the gypsum powder, what will happen to the setting

time? a. Reduced slightly b. Reduced significantly c. Extended slightly d. Extended significantly ANS: C

A B C D

Feedback Borax will not reduce the setting time in any way. Borax will not reduce the setting time in any way. A 2% solution of borax can extend the setting time by several hours. Borax, a chemical with the formula Na2B4O7 • 10H2O, is a chemical that will extend the setting time of some gypsum products by several hours if added to the powder at a concentration of 2%.

DIF: Knowledge REF: p. 121 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 31. Water-powder ratio is defined as the amount of water in

powder in . a. ounces; ounces b. ounces; grams c. milliliters; ounces d. milliliters; grams ANS: D

Feedback

added to the amount of

A B C D

Manufacturers base their measurements in milliliters of fluid and in grams of powder. Manufacturers base their measurements in milliliters of fluid and in grams of powder. Manufacturers base their measurements in milliliters of fluid and in grams of powder. The water-powder ratio for a material is defined as the amount of water in milliliters added to 100 g of powder.

DIF: Knowledge REF: p. 121 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 32. If the mixing water temperature a. is above 37.5° C b. is below 37.5° C c. reaches 100° C

the hemihydrate will not set.

ANS: C

B C

Feedback If the room temperature (20° to 25° C) is raised up to body temperature (37.5° C), the setting time decreases. The temperature of the mixing water has a similar effect. If the mixing water teT mE pS erT atB urAe NisKrS aiE seLdLaE boRv. eC 37O.5M° C, the setting time will increase. If the mixing water temperature reaches 100° C, the hemihydrate will not set at all.

DIF: Knowledge REF: p. 122 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 33. Which use of gypsum is hardness and abrasion resistance especially important for? a. Orthodontic models b. Study models c. Dies d. Casts ANS: C

A B C

Feedback Orthodontic models do not require the same level of hardness and abrasion resistance. Study models do not require the same level of hardness and abrasion resistance. Increased hardness and abrasion resistance are especially important for die

materials, in which extreme accuracy is needed to ensure the proper fit of crowns and inlays. Casts do not require the same level of hardness and abrasion resistance.

DIF: Knowledge REF: p. 123 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 34. Which of the following represents the time period designated for the initial set of gypsum? a. Pour begins until the pour is complete. b. Powder is added to the water until mixing is complete. c. Powder is added to the water until the pour is complete. d. Powder is added to the water until the material cannot be used. ANS: D

A B C D

Feedback The time for pouring is included in the 5-minute time frame. The time for mixing water and powder should be about 1 minute. The time for mixing water and powder and pouring to be complete should be about 5 minutes. The initial setting time is the interval between the time the water and powder are mixed and the time that the mix can no longer be poured into a mold or impression.

DIF: Knowledge REF: p. 122 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 35. How is the final setting time of gypsum defined? a. The point where the gypsum can be removed without distortion b. The point where the gypsum can be removed without fracture c. The point where the exothermic reaction is complete d. All of the above e. Only A and B ANS: E

A B C D E

Feedback A and B are both correct answers. A and B are both correct answers. The exothermic reaction is not an accurate predictor of set. A and B are the only correct answers. The final setting time is defined as the time at which the conversion of the hemihydrate to dihydrate is essentially complete. Clinically this means that the gypsum then can be removed from its impression or otherwise manipulated

without distortion or fracture. DIF: Knowledge REF: p. 122 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 36. The inherent roughness limits the ability of gypsum materials to capture the finest details of

impressions. Reproduction of detail is sufficient for most applications. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

B C D

Feedback The inherent roughness limits the ability of gypsum materials to capture the finest details of impressions, although from a practical standpoint, the reproduction of detail is sufficient for most applications. Both statements are correct. Both statements are correct. Both statements are correct.

DIF: Comprehension REF: p. 124 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 37. Proper wetting occurs when gypsum is poured against a

-based impression material

such as . a. water; alginate b. water; addition silicone c. non-water; alginate d. non-water; addition silicone ANS: A

A B C D

Feedback When gypsum is poured against a water-based impression material such as alginate, good wetting occurs, and the detail of reproduction is good. When gypsum is poured against a water-based material such as an addition silicone, the wetting may be reduced. When gypsum is poured against a non–water-based material such as an addition silicone, the wetting may be reduced. When gypsum is poured against a non–water-based material such as an addition silicone, the wetting may be reduced.

DIF: Comprehension

REF: p. 123

OBJ: 10

TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 38. If gypsum materials are not adequately spatulated, a. strength b. accuracy c. abrasion resistance d. dimensional change

suffers.

ANS: D

A B C D

Feedback Many users of gypsum materials do not spatulate the gypsum adequately, and the physical properties such as strength suffer as a result. Accuracy is attributed to the impression. Abrasion resistance will depend on the type of gypsum used. Dimensional change is attributed to the impression.

DIF: Knowledge REF: p. 123 OBJ: 10 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 39. Dies of epoxy for use in fabrication of crowns, bridges, and inlays can be poured into alginate.

ES Epoxy dies are tougher andTm orT eB abArN asK ioSnEreLsL isE taR nt.thCaO nMhigh-strength stone dies, and they are more accurate and stable dimensionally. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

A B C D

Feedback Epoxy is used with elastomeric materials. Epoxy is used with elastomeric materials. Epoxy dies are not as dimensionally stable. Dies of epoxy for use in fabrication of crowns, bridges, and inlays can be poured into polyether, polysulfide, or silicone elastomeric impression materials, although a separator must be used with polysulfide impressions to prevent the epoxy from bonding to the impression. Epoxy dies are tougher and more abrasion resistant than high-strength stone dies, but they are not as accurate or as stable dimensionally.

preparations for study casts 40. Which of the following is not a method for pouring a gypsum model base? a. Pile mound onto a smooth, non-stick surface. b. Wrap the impression with boxing wax. c. Over-pour the impression and invert. d. Fill a base former. ANS: C

A B C D

Feedback Place extra material on a smooth surface, such as a glass slab, and invert the impression. Wrap the impression in boxing wax; then pouring to the top of the wax box provides an adequate base. Over-pouring the impression will not provide an adequate base. Base formers allow for an adequate base to work with.

DIF: Knowledge REF: p. 125 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 41. Which statement is correct regarding epoxy dies? a. Works best with alginate b. Low resistance to scratches c. They are dimensionally stable. d. They are a two-component system. ANS: D

A B C D

Feedback Epoxy die materials work best with elastomeric materials. They are harder than die stone and resist scratching. They are not as dimensionally stable as die stone. Epoxy die materials are a two-component system.

DIF: Knowledge REF: p. 128 OBJ: 15 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 42. Dies can be constructed using digital data. Gypsum dies cannot be scanned for milling

procedures. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect.

ANS: B

A B C D

Feedback Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect.

DIF: Comprehension REF: p. 128 OBJ: 16 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts SHORT ANSWER 1. Explain the differences between a study model, a cast, and a die. List the different types of

materials associated with each. ANS:

Study models are used to observe the patient’s oral structures. Study models are often poured in plaster. A cast is a working model. Casts of teeth are used to make orthodontic retainers, and casts of the remaining ridges in the edentulous patient are used to make dentures. Casts are typically poured in stone. Dies are highly accurate replicas of a single tooth and generally are used to make metal crowns or inlays. They are made from high-strength dental stone.

TESTBANKSRE L:LE EF p.R. 11C8OM OBJ: 1 DIF: Comprehension TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts 2. Once the impression is removed from the mouth, list the steps for loading the impression tray. ANS:

1. Rinse the model with water to remove any debris or blood from the surface of the impression. Remove excess water from the impression. 2. Add a small amount of mixed gypsum material in one corner of the impression. 3. Place the impression gently on a vibrator to remove bubbles and then continue to add gypsum material. 4. Use a model former or use boxing wax to obtain the proper shape of the arch. 5. Add gypsum to the model former and invert the filled impression and place in the gypsum base. Do not trap the tray in set gypsum. 6. Allow gypsum material to set for 60 minutes until cool and dry before removing model. 7. Separate model from the impression. 8. Immediately clean the tray unless it is disposable. DIF: Analysis REF: p. 125 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 3, c. gypsum products

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.3 Making impressions and preparations for study casts

Chapter 10: Waxes Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Dental waxes are usually a. inorganic; high b. inorganic; low c. organic; high d. organic; low

molecules that have

molecular weights.

ANS: C

A B C D

Feedback Component waxes are organic. Component waxes are organic and have high molecular weights. Component waxes in dental waxes are usually organic molecules with high molecular weights. Component waxes have high molecular weights.

DIF: Comprehension REF: p. 131 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Which of the following waT xE esSaT reBcAatNegKoSriE zeLdLaE sR pa.ttCerOnMwaxes? a. Baseplate wax b. Utility wax c. Inlay wax d. A, B, and C e. A and C ANS: E

A B C D E

Feedback Both A and C are correct. Utility wax is a processing wax. Both A and C are correct. Only A and C are correct. Pattern waxes include casting waxes, baseplate wax, and inlay wax.

DIF: Comprehension REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. Which of the following waxes are categorized as processing waxes? a. Beading wax b. Sticky wax

c. Inlay wax d. A, B, and C e. A and B ANS: E

A B C D E

Feedback A, and B are correct. A, and B are correct. Inlay wax is a pattern wax. Beading wax and sticky wax are categorized as processing waxes. Inlay wax is a pattern wax. A, and B are correct.

DIF: Comprehension REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. Organic molecules in waxes are composed primarily of long chains containing carbon,

hydrogen, and oxygen. The long chains allow waxes to be flexible at room temperature or sticky as solids or liquids. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Both statements are correct. Both statements are correct. Both statements are correct. Both statements are correct.

DIF: Comprehension REF: p. 131 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. Which statement(s) is/are correct about waxes? a. Melt at a single temperature b. Are mixtures of different components c. Do not have a discrete melting point at one temperature d. A and B are correct. e. B and C are correct. ANS: E

Feedback Waxes have a melting range dependent upon their properties and purposes.

B C D E

B and C are both correct. B and C are both correct. B and C are both correct. Waxes do not have a discrete melting point at one temperature. They are mixtures of different components.

DIF: Comprehension REF: p. 132 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. Which of the following statements is correct about the property of flow for dental waxes? a. Flow is highly dependent on temperature and time. b. For pattern waxes, flow at room temperature is a highly desirable property. c. For processing waxes, flow at room temperature is a highly desirable property. d. A and B are true statements. e. A and C are true statements. ANS: E

A B C D E

Feedback Both A and C are correct. Pattern wax must flow at higher than room temperature to prevent distortion. Both A and C are correct. Both A and C are correct. Flow is highly dependent on temperature and time. For processing waxes, flow at room temperature iT sE aS hiT ghBlyAN deKsiSraEbL leLpE roRp. erC tyO, M but for pattern waxes it is not.

In general, waxes have the highest coefficient of thermal expansion of any dental material. Ceramics have a lower coefficient of thermal expansion, which is 20 times lower than that of pattern wax. Gold alloy has a lower coefficient of thermal expansion. Silver amalgam has a lower coefficient of thermal expansion.

DIF: Knowledge

REF: p. 133

OBJ: 2

TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. How should wax be manipulated in order to reduce the amount of stress on the material? a. Wax should be burnished at temperatures well below its melting range. b. Wax should be carved at temperatures well below its melting range. c. Wax patterns should be carved with warm instruments. d. Melted wax should be added in large increments. ANS: C

A B C D

Feedback Wax should not be carved or burnished below melting range. Wax should not be carved or burnished below melting range. In order to prevent residual stresses from forming, wax patterns should be carved with warm instruments. Melted wax should be added in small increments.

DIF: Knowledge REF: p. 133 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. Wax carving instruments should be at what temperature when in use? a. 7° C b. 17° C c. 27° C d. 37° C e. 47° C ANS: D

A B C D E

Feedback The wax is not warm enough to carve at 7° C, which could cause residual stress. The wax is not warm enough to carve at 17° C, which could cause residual stress. The wax is not warm enough to carve at 27° C which could cause residual stress. Wax patterns should be carved with instruments at 37° C. The wax is too warm to carve at 47° C.

DIF: Knowledge REF: p. 133 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. What is the time frame for investing a wax pattern once it has been completed? a. At least a week b. 24 hours c. Between 5 and 30 minutes d. Less than 5 minutes

ANS: C

A B C D

Feedback The longer the pattern sits, the more stresses are released. The longer the pattern sits, the more stresses are released. The time between finishing and investing a wax pattern should be over 5 but less than 30 minutes. Less than 5 minutes does not allow adequate cooling without distortion.

DIF: Knowledge REF: p. 133 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. Which of the following type of wax is used to fabricate wax patterns for crowns and other

indirect restorations? a. Casting wax b. Boxing wax c. Utility wax d. Inlay wax ANS: D

A B C D

Feedback Casting wax is used to form metallic frameworks. Boxing wax is a processing wax. Utility wax is a proceT ssE inSgTwBaA x.NKSELLER.COM Inlay wax is used to fabricate wax patterns for crowns, inlays, and bridges.

DIF: Knowledge REF: p. 133 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. Which of the following is not a mineral wax? a. Paraffin b. Ceresin c. Carnauba d. Both A and B are correct. ANS: C

A B C D

Feedback Paraffin is a mineral wax. Ceresin is a mineral wax. Carnauba is a plant wax. C is the only correct answer.

DIF: Knowledge REF: p. 133 OBJ: 1| 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver,

and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. When is casting wax used? a. Fabricate wax patterns for crowns, inlays, and bridges b. Build the contours of a denture c. Register the details of soft tissue in a functional state d. Form the wax pattern of the metallic framework for removable partial dentures ANS: D

A B C D

Feedback Inlay wax is used to fabricate crowns, inlays, and bridges. Baseplate wax builds the contours of a denture. Corrective wax registers details of tissue in a functional state. Casting wax is used to form the wax pattern of the metallic framework of removable partial dentures.

A B C D

Feedback Baseplate wax is available in sheets. Baseplate wax is available in sheets. Baseplate wax is available in sheets. Baseplate wax is available in sheets.

DIF: Knowledge REF: p. 133 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. Which type of wax is used to hold the position of denture teeth before the denture is processed

in acrylic? a. Sticky wax b. Utility wax c. Baseplate wax d. Corrective impression wax ANS: C

A B C D

Feedback Sticky wax is used to adhere materials together. Boxing and utility waxes are used primarily in taking and pouring impressions. Baseplate wax is used to hold the position of denture teeth before the denture is processed in acrylic. Corrective impression wax is used on soft tissue.

DIF: Knowledge REF: p. 133 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 16. What does resin have that is different than inlay wax when it comes to fabrication of crowns

and bridges? a. Available as chemically cured composite resins b. Higher strength than dental waxes c. Higher flow than dental waxes d. Residue when they burn out ANS: B

A B C D

Feedback Resins are light-cured. Resins used as patterns for dental restorations have higher strength than dental waxes. Resins have lower flow. Resins do not leave reTsiEdS ueToBnAbN urKnS ouEt.LLER.COM

DIF: Knowledge REF: p. 134 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. Which of the following statements is true of pattern waxes and resins? a. They must have a melting range lower than the environment in which the pattern is

made. b. Too high of a melting range may make development of residual stresses a problem. c. They must possess high flow at their working temperature. d. All pattern waxes and resins must burn out with a residue. ANS: D

A B C D

Feedback Too high of a melting range may make development of residual stresses a problem. Their melting range is higher. They must be low flow at working temperature. There should be no residue after burnout.

DIF: Comprehension

REF: p. 134

OBJ: 5

waxes are used primarily in taking and pouring impressions. Sticky Utility Boxing Corrective impression Both B and C are correct.

ANS: E

A B C D E

Feedback Sticky wax is used to adhere materials together. Utility waxes are used primarily in taking and pouring impressions. Boxing waxes are used primarily in taking and pouring impressions. Corrective impression wax is used on soft tissue. Boxing and utility waxes are used primarily in taking and pouring impressions.

DIF: Comprehension REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. Which type of wax may be molded around an unpoured impression to help contain the stone

when it is vibrated into theTim prT esBsiAoN n?KSELLER.COM ES a. Inlay wax b. Sticky wax c. Boxing wax d. Corrective impression wax ANS: C

A B C D

Feedback Inlay wax is used to fabricate crowns, inlays, and bridges. Sticky wax is used to adhere materials together. Boxing wax may be molded around an unpoured impression to help contain the stone when it is vibrated into the impression. Corrective impression wax is used on soft tissue.

DIF: Knowledge REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Utility and periphery waxes are about a. 0.1 mm b. 0.5 mm c. 0.1 cm d. 0.5 cm

in diameter.

ANS: D

A B C D

Feedback 1 mm is too small. 0.5 mm is too small. This is the thickness of boxing wax. Utility and periphery waxes are about 0.5 cm in diameter.

DIF: Knowledge REF: p. 134 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Which statement is true about sticky wax? a. Soft and pliable at room temperature b. Hard and brittle at room temperature c. Used to assemble metallic or resin pieces temporarily in position d. Both A and C e. Both B and C ANS: E

A B C D E

Feedback Sticky wax is hard and brittle at room temperature. B and C are both correct answers. B and C are both correct answers. B and C are both corrT ecEt S anTsB wA erN s.KSELLER.COM Sticky wax is hard and brittle at room temperature. It is used to assemble metallic pieces or resin pieces temporarily in position.

DIF: Comprehension REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Sticky wax will break rather than become distorted if the assembled pieces move. The pieces

of sticky wax cannot be rejoined in their proper relationship therefore they need to be replaced. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B C D

DIF: Comprehension REF: p. 135 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Which type of wax is used as a wax veneer over an original impression to register the detail of

soft tissues in a functional state? a. Utility wax b. Boxing wax c. Baseplate wax d. Corrective impression ANS: D

A B C D

Feedback Utility wax is used primarily for taking and pouring impressions. Utility wax is used primarily for taking and pouring impressions. Baseplate wax is used to reproduce the contours of the arch and to hold teeth for the patient to try prior to fabrication. Corrective impression wax is used as a wax veneer over an original impression to register the detail of soft tissues in a functional state.

DIF: Knowledge REF: p. 135 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. The flow of corrective impression wax at mouth temperature is a. 10 b. 25 c. 50 d. 75 e. 100

ANS: E

Feedback Flow rates that low would produce less than accurate results. At 100%, however, corrective impression wax is easily distorted when removing it from the oral cavity. Flow rates that low would produce less than accurate results. At 100%, however, corrective impression wax is easily distorted when removing it from the oral cavity. Flow rates that low would produce less than accurate results. At 100%, however, corrective impression wax is easily distorted when removing it from the oral cavity. Flow rates that low would produce less than accurate results. At 100%, however, corrective impression wax is easily distorted when removing it from the oral cavity.

The flow of corrective impression wax at mouth temperature is 100%.

DIF: Knowledge REF: p. 136 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. Which of the following waxes may be used for bite registration? a. Baseplate wax b. Bite-registration wax c. 28-gauge casting wax d. A, B, and C e. A and C ANS: D

A B C D E

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. Baseplate wax, 28-gauge casting wax, and bite-registration wax may all be used for bite registration. A, B, and C are all correct.

DIF: Comprehension REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materialT s,E inSclT udBinAgNbK utSnE otLliL mE itR ed.toC2O.M dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. What are pattern or casting waxes used to fabricate? a. Inlays b. Veneers c. Crowns d. A, B, and C e. A and C are both correct. ANS: E

A B C D E

Feedback A and C are both correct. Veneers are not constructed using the lost-wax technique. A and C are both correct. Only A and C are correct. Pattern waxes include casting waxes, baseplate wax, and inlay wax. They are used to fabricate a restoration using the lost-wax technique.

27. Which type of wax would include boxing, utility, and sticky waxes? a. Processing b. Baseplate c. Pattern d. Inlay ANS: A

A B C D

Feedback Processing waxes include boxing, beading, utility, and sticky wax. These waxes are used as auxiliary materials. Baseplate wax is used to replicate the baseplate for a full denture. A pattern wax is used to fabricate castings using the lost-wax technique. Inlay wax is used to construct inlays, crowns, and bridges.

DIF: Knowledge REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. Waxes have a specific melting point. Waxes are single-component materials. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

A B C D

Feedback Because waxes are mixtures of different components, they do not melt at a single temperature and do not have a melting point. Rather, they have a melting range. Because waxes are mixtures of different components, they do not melt at a single temperature and do not have a melting point. Rather, they have a melting range. Because waxes are mixtures of different components, they do not melt at a single temperature and do not have a melting point. Rather, they have a melting range. Because waxes are mixtures of different components, they do not melt at a single temperature and do not have a melting point. Rather, they have a melting range.

temperatures, waxes hardly flow at all, but as the temperature approaches the melting of the wax, the flow increases. a. low; point b. low; range c. high; point d. high; range ANS: B

A B C D

Feedback At low temperatures, wax becomes easier to use, but it does not flow until it enters its melting range. At low temperatures, waxes hardly flow at all, but as the temperature approaches the melting range of the wax, the flow increases. At low temperatures, wax becomes easier to use, but it does not flow until it enters its melting range. At low temperatures, wax becomes easier to use, but it does not flow until it enters its melting range.

the coefficient of thermal expansion for waxes, the the wax is heated. a. higher; lower b. higher; greater c. lower; lower d. lower; greater

the expansion as

ANS: B

B C D

Feedback The higher the coefficTieEnS t oTfBthAeN rm the greater the rate of KaSl EexLpLanEsRio.nCisO, M expansion as the wax is heated. The expansion rate increases. It does not slow down. The higher this coefficient is, the greater the expansion as the wax is heated. The lower the coefficient of thermal expansion is, the lower the rate of expansion when heated. The lower the coefficient of thermal expansion is, the lower the rate of expansion when heated.

cooling, bending, carving, or other manipulation. Manipulation of wax puts molecules of the wax into positions that they like and can change because of their solid state. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

Feedback Residual stress is stress remaining in a wax as a result of manipulation during heating. When the wax is in its solid state it cannot change its position, resulting in stress. Residual stress is stress remaining in a wax as a result of manipulation during heating, cooling, bending, carving, or other manipulation. Manipulation of wax puts molecules of the wax into positions that they do not like but cannot change because of their solid state. Residual stress is stress remaining in a wax as a result of manipulation during heating. When the wax is in its solid state it cannot change its position, resulting in stress. Residual stress is stress remaining in a wax as a result of manipulation during heating. When the wax is in its solid state it cannot change its position, resulting in stress.

DIF: Comprehension REF: p. 133 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. The release of stress at higher temperatures will cause a. no b. reversible c. irreversible d. insignificant

deformation.

ANS: C

A B C D

Feedback Higher temperatures will cause irreversible deformation of the wax pattern. Higher temperatures will cause irreversible deformation of the wax pattern. The release of residual stress at higher temperatures causes an irreversible deformation that can destroy the fit of a wax pattern. Higher temperatures will cause irreversible deformation of the wax pattern.

DIF: Knowledge REF: p. 133 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 33. The lost-wax technique uses a. inlay b. casting c. baseplate d. only A and B ANS: D

Feedback A and B are both correct.

wax to produce crowns, inlays, and veneers.

B C D

A and B are both correct. Baseplate wax is a pattern wax, but it is not used in the lost-wax technique. Only A and B are correct.

DIF: Comprehension REF: p. 133 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. Organic molecules in some waxes contain long-chain elements. Which of the following is not

part of that group? a. Hydrogen b. Carbon c. Oxygen d. Silica ANS: D

A B C D

Feedback Hydrogen is an organic long-chain molecule. Carbon is an organic long-chain molecule. Oxygen is an organic long-chain molecule. Silica is a mineral.

DIF: Comprehension REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materialT s,E inSclT udBinAgNbK utSnE otLliL mE itR ed.toC2O.M dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 35. Manufactured in ready-made shapes, a. inlay b. casting c. baseplate d. corrective

wax is used for partial denture frameworks.

ANS: A

A B C D

Feedback Inlay wax is used to construct inlays, crowns, and bridges. These waxes are used to form the wax pattern of the metallic framework of removable partial dentures. They are available in sheets and in ready-made shapes, which are convenient for making the wax pattern of the partial denture. Baseplate wax is used to replicate the baseplate for a full denture. Corrective wax is used to fill undercuts.

36. Of the following, which is not an advantage of using resins versus waxes to manufacture

crowns, bridges, and inlays? a. Wax is stronger. b. Wax is weaker. c. Wax leaves residue. d. Wax burns out cleanly. e. Only A and D are advantages. f. Only B and C are advantages. ANS: D

A B C D E F

Feedback Waxes are weaker than resin, and they may not burn out as cleanly. Waxes are weaker than resin. Waxes are weaker than resin, and they may not burn out as cleanly. Waxes do not always burn out cleanly. D is the only correct answer. D is the only correct answer.

DIF: Comprehension REF: p. 131 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 37. What is the purpose of sticky wax? a. Temporarily hold metal together b. Correct an original impTreEsS siT onBANKSELLER.COM c. Gain accurate articulation d. Maintain a specific pattern ANS: A

B C D

Feedback Sticky wax is used commonly to assemble metallic or resin pieces temporarily in position or to seal a plaster splint to a stone cast in the process of forming porcelain facing. Correction impression wax corrects an original impression. Bite-registration wax gains accurate articulation. Inlay wax maintains a specific pattern.

DIF: Knowledge REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. Which of the following is an advantage of casting wax? a. Flows easily b. Slight tackiness c. No residual stress d. Can be light cured

ANS: B

A B C D

Feedback The material has very little flow properties. It has a slight tackiness to help hold the pattern in place. Nearly all waxes react to some sort of stress, usually the result of thermal changes. Resin materials are light cured.

DIF: Knowledge REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39. The flow of wax increases as the temperature decreases. The release of stress in a wax pattern

leads to distortion. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorreT ctE; S stT atB em t 2SiEs L coLrE reR ct. . COM AeNnK Statement 1 is incorrect; statement 2 is correct.

A B C D

Feedback A type II baseplate wax is used in most climates. A type III baseplate wax is harder and recommended for use in tropical climates. A type I baseplate wax is used for contouring dentures. Inlay wax maintains a specific pattern.

DIF: Knowledge REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver,

and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast processing waxes with pattern waxes. Give examples of each. ANS:

Processing waxes are used in various auxiliary roles in the fabrication of models and impressions and in soldering. Several processing waxes deserve special comment because they are widely used. Processing waxes include utility, boxing, sticky, bite registration, and corrective waxes. Pattern waxes are used to create a model of a dental restoration such as a crown or partial denture that eventually is cast using the lost-wax technique. Pattern waxes include baseplate, inlay, and casting waxes. DIF: Analysis REF: p. 134 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. List the five important properties of waxes, and explain why each is essential to the success of

the final outcome. ANS:

Melting range, excess residue, flow, thermal expansion, and residual stress are the five important properties of waT xeEs.S TBANKSELLER.COM Melting range: Because waxes are mixtures of different components, they do not melt at a single temperature and do not have a melting point. It is essential to know what melting range applies to each wax you work with. Flow: Flow is the change in shape under an applied force. It is caused by the slippage of the long-chained wax molecules over each other. Flow is highly dependent on temperature and time. Excess residue: Pattern and inlay waxes are used to make indirect placement restorations such as crowns and partial denture framework. The patterns are invested and the wax pattern is burned out in order to fabricate the restoration. It is important that the wax burn out completely or the final product will be deficient. Thermal expansion: When heated, waxes expand significantly, and they all expand at different rates. This information is important based on the type of wax used and the purpose of the usage. Residual stress: Residual stress is stress remaining in a wax as a result of manipulation during heating, cooling, bending, carving, or other manipulation. Manipulation of wax puts molecules of the wax into positions that they do not like but cannot change because of their solid state. DIF: Analysis REF: p. 134 OBJ: 1| 2|3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 2. dental waxes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

Chapter 11: Casting Alloys, Wrought Alloys, and Solders Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. a. b. c. d.

alloys are first cast but then shaped by mechanical force into their final forms. Wrought Dental casting Resin composite Ceramic bonding

ANS: A

A B C D

Feedback Wrought alloys are first cast but then shaped by mechanical force into their final forms. Crowns are formed prior to casting in metal. Resin bonding is not a casting process. Ceramic bonding is not a casting process.

DIF: Knowledge REF: p. 138 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. What factors determine theTdEeS fini tioAnNoKf S aE noLbLleEm TB Re.taCl?OM a. Inability to be used in an alloy b. Indistinct melting point c. Resistance to corrosion d. Lack of malleability ANS: C

A B C D

Feedback Noble metals, such as gold, are mixed as alloys with other metals. These alloys have a specific melting point. Noble metals are defined by their resistance to corrosion. They are malleable.

DIF: Knowledge REF: p. 138 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. Which of the following is a noble metal? a. Zinc b. Nickel c. Copper d. Titanium

e. Palladium ANS: E

A B C D E

Feedback Zinc is a base metal. Copper is a base metal. Nickel is a base metal. Titanium is a base metal. Palladium is a noble metal.

DIF: Knowledge REF: p. 139 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. Which of the following statements is true concerning noble and base metals? a. Silver will not corrode in the oral environment. b. The term precious metal is preferred over noble metal. c. Seven noble metals are commonly used in dental casting alloys. d. Base metals are required in dental alloys for strength, flexibility, and wear

resistance. e. Base metals are viewed in dentistry as bad metals and are not used in dental

restorations. ANS: D

A B C D E

Feedback Nickel tarnishes. Noble metal is the preferred term. There are three noble metals. Base metals are required in alloys to improve properties of noble metals. Base metals are required in dental alloys for strength, flexibility, and wear resistance.

Why is gold used in dental alloys? Its relatively high melting point Its resistance to corrosion Its yellow color A, B, and C A and C

a. b. c. d. e.

ANS: B

Feedback It has a relatively low melting point.

B C D E

Gold is used for dental alloys primarily because of its resistance to corrosion. Although gold is yellow, many gold-containing alloys are not. Only A is correct. Only A is correct.

DIF: Comprehension REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. Define malleability. a. The ability to be mechanically formed b. The ability to be drawn into a wire c. Corrosion resistance d. Tarnish resistance ANS: A

A B C D

Feedback Malleability is defined as the ability to be mechanically formed. Wrought metals are drawn into wire. Corrosion is a chemical reaction. Tarnish is a discoloration.

DIF: Knowledge REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, includT inEgS buTtB n tN limS K iteEdLtoLUEnRlist.eCdOtoMpic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. Why is silver added to casting alloy? a. Enhance bond strength b. Prevent oxidation c. Harden the gold d. Prevent tarnish ANS: C

A B C D

Feedback Iron enhances bond strength. Zinc is used to prevent oxidation. Silver is used to harden alloys. Gold does not tarnish.

DIF: Knowledge REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. When a molten (liquid) alloy freezes, crystals a. dissolve; disperse b. form; dissolve

and

as the material cools.

c. grow; disperse d. form; grow ANS: D

A B C D

Feedback Crystals are a by-product of the molten/cooling process. They do not dissolve or disperse. Crystals are a by-product of the molten/cooling process. They grow but do not disperse. Crystals are a by-product of the molten/cooling process. They form but do not dissolve. When a molten alloy freezes, crystals form and grow as the material cools.

DIF: Knowledge REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. Which of the following is correct about palladium? a. Is much harder than gold b. Has poor corrosion resistance c. Has a much lower melting point than gold d. May be used in pure form for dental restorations e. Both B and C ANS: C

A B C D E

Feedback It has excellent corrosion resistance. It has a much higher melting point. Palladium is much harder than gold. It is not used in pure form for dental restorations. C is the only correct answer.

DIF: Comprehension REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. Which of the following statements is(are) true of dental alloy crystal structure and grains? a. The areas between crystals in an alloy are called grain boundaries. b. A large grain size is generally more desirable than a large grain size for dental

alloy properties. c. If an alloy is rolled into a sheet or drawn into a wire, the grain structure takes on a

fibrous appearance. d. A, B, and C are correct. e. B and C are correct. ANS: E

A B C D

Feedback A small grain size is generally more desirable than a large grain size, because the alloy’s mechanical properties are better. B and C are correct answers. B and C are correct answers. The lines between crystals are called grain boundaries. If an alloy is rolled into a sheet or drawn into a wire, the grain structure takes on a fibrous appearance and is called a wrought form. B and C are correct answers.

DIF: Comprehension REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. If an alloy contains 40 wt % gold, 20 wt % palladium, 10 wt % platinum, and 30 wt % copper,

the nobility would be a. 10 b. 20 c. 30 d. 40 e. 75

wt %.

ANS: E

Feedback Percent nobility is theTaE mSoT unBt A oN f nKoS blEeLmLeE taR ls.wCitO hiMn the total alloy mixture. High-noble metals must be at least 60% noble metals with a minimum of 40% as gold. Percent nobility is the amount of noble metals within the total alloy mixture. High-noble metals must be at least 60% noble metals with a minimum of 40% as gold. Percent nobility is the amount of noble metals within the total alloy mixture. High-noble metals must be at least 60% noble metals with a minimum of 40% as gold. Percent nobility is the amount of noble metals within the total alloy mixture. High-noble metals must be at least 60% noble metals with a minimum of 40% as gold. If an alloy contains 40% gold, 20% palladium, 10% platinum, and 30% copper, the nobility would be 75%.

DIF: Analysis REF: p. 144 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. An alloy liquidus is defined as the temperature at which a. all of the alloy melts b. an alloy begins to melt c. all of the alloy freezes upon cooling

d. some of the alloy freezes upon cooling ANS: A

A B C D

Feedback Liquidus is defined as the temperature at which all of the alloy melts upon heating. Alloy is not completely melted to a liquid state. All of the alloy freezing upon cooling is the solidus of the alloy. Alloy is not completely frozen to a solid state.

DIF: Knowledge REF: p. 145 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. Which of the following statements is(are) true of the density of an alloy? a. The alloy with the highest density weighs the most. b. High-density alloys are generally the most difficult to cast. c. High-density alloys cost more than low-density alloys, because more mass is

present in any given volume of restoration. d. A, B, and C are true statements. e. A and C are true statements. ANS: E

A B C D E

Feedback A and C are both corrT ecEt.STBANKSELLER.COM High-density alloys are generally the easiest to cast. A and C are both correct. Only A and C are correct. The alloy with the highest density weighs the most, and high-density alloys cost more than low-density alloys, because more mass is present in any given volume of restoration.

DIF: Comprehension REF: p. 143 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 14. According to the ADA classification for dental casting alloys, high-noble alloys must have a

noble metal content of at least a. 20 b. 40 c. 60 d. 80 e. 90 ANS: C

Feedback

% by weight.

A B C D E

Noble alloys must have a noble content of at least 25%. There is no specific standard for gold content. This is the gold content standard for high-noble alloys. According to the ADA classification for dental casting alloys, high-noble alloys must have a noble metal content of at least 60% by weight. Contents at 80% are too high to be usable. Contents at 90% are too high to be usable.

DIF: Knowledge REF: p. 145 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. Of all the alloys, which alloys are the most difficult to cast and polish? a. High-noble b. Base-metal c. Noble gold-based d. Noble silver-based e. Noble palladium-based ANS: B

A B C D E

Feedback High-noble and noble metals polish better than base metals. Base-metal alloys are the most difficult to cast and polish of all the alloys. High-noble and noble metals polish better than base metals. High-noble and nobleTmEeStaTlsBpAoN lisKhSbE etL teLr E thR an.bCaOseMmetals. High-noble and noble metals polish better than base metals.

Which of the following statements is true about ceramics used in restorative dentistry? a. The solidus of the alloy must be lower than the fusion temperature of the ceramic. b. The solidus of the alloy must be higher than the fusion temperature of the ceramic. c. The coefficient of thermal expansion for the alloy should be less than that of the ceramic. d. Both A and C e. Both B and C ANS: B

A B

Feedback Ceramic has a high working temperature; therefore the alloy’s melting point must be higher than the ceramic’s melting point. For ceramic-bonding alloys, the solidus of the alloy must be higher than the fusion temperature of the ceramic, and the coefficient of thermal expansion for the alloy should be greater than that of the ceramic.

C D E

The coefficient of thermal expansion should be similar in both materials to prevent fracture. B is the only correct answer. B is the only correct answer.

DIF: Comprehension REF: p. 147 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. How can greening of ceramic be avoided? a. Select an appropriate alloy. b. Periodic cleaning of the ceramic oven c. Firing the restoration at the appropriate temperature d. A, B, and C e. Only A and C are correct. ANS: D

A B C D

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. Greening of ceramic may be avoided by selecting an appropriate alloy, firing the restoration at the appropriate temperature, and periodic cleaning of the ceramic oven. A, B, and C are all coT rrE ecSt.TBANKSELLER.COM

DIF: Comprehension REF: p. 147 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. What is the best solution to the problem of debonding of ceramic from a ceramic–alloy

restoration after cementation in the mouth? a. Bond direct composite to the metal substructure. b. Refire new porcelain to the metal while the crown remains in the mouth. c. Remove the crown, refire new porcelain to the metal, and then re-cement the crown. d. Prevent debonding by selection of compatible alloys and ceramics and the proper manipulation of these materials during fabrication. ANS: B

A B C

Feedback If a ceramic restoration fails in service, the only effective solution is to remake the restoration. If a ceramic restoration fails in service, the only effective solution is to remake the restoration. The best solution to the problem of debonding of ceramic from a ceramic–alloy

restoration after cementation in the mouth is to prevent debonding by selection of compatible alloys and ceramics and the proper manipulation of these materials during fabrication. If a ceramic restoration fails in service, the only effective solution is to remake the restoration.

DIF: Knowledge REF: p. 150 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. The correct order of firing to create sintered alloy composites is firing

1. of a ceramic that mediates ceramic–alloy bonding. 2. to create a spongy coping of high-noble metals. 3. of a lower fusing alloy that is absorbed by capillary action. a. 1, 2, 3 b. 2, 1, 3 c. 3, 1, 2 d. 1, 3, 2 e. 2, 3, 1 ANS: E

A B C D E

Feedback Steps performed outside of the proper order would cause failure of the process. Steps performed outsiTdE eS ofTthBeApNroKpS erEoLrdLeEr R w. ouCldOM cause failure of the process. Steps performed outside of the proper order would cause failure of the process. Steps performed outside of the proper order would cause failure of the process. The correct order of firing to create sintered alloy composites is firing in order to create a spongy coping of high-noble metals, firing of a lower fusing alloy that is absorbed by capillary action, and then firing of a ceramic that mediates ceramic– alloy bonding.

DIF: Analysis REF: p. 147 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Wrought alloys have a grain structure often described as fibrous. The fibrous structure is

responsible for increased yield strength and hardness compared with the cast form of the alloys. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

Feedback

A B C D

Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is correct.

DIF: Comprehension REF: p. 150 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. What are PGP wires used for? a. Endodontic files b. Orthodontic wires c. Clasps in removable partial dentures d. Substructures for fixed partial dentures ANS: C

A B C D

Feedback Endodontic files are wrought metals of stainless steel or titanium. Orthodontic wires are base metals. PGP wires are used for clasps in removable partial dentures. PGP stands for platinum-gold-palladium. Substructures are cast metals.

DIF: Knowledge REF: p. 150 OBJ: 4 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. When are solders used in dentistry? a. Clasp wire to a partial denture framework b. Orthodontic wire to a band in full treatment c. Bond two units of a fixed partial denture together after each is cast separately. d. A, B, and C e. A and C ANS: E

A B C D E

Feedback A and C are correct. Orthodontic wires are not soldered to the band during full orthodontic treatment. They are held in place with ligature ties or elastics. A and C are correct. A and C are correct. Solders may be used in dentistry in order to join an orthodontic wire to a band in construction of a space maintainer, a clasp wire to a partial denture framework, or two units of a fixed partial denture together after each is cast separately. Each of these procedures uses different solders and techniques.

DIF: Comprehension REF: p. 150 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Biocompatibility of dental alloys is often based on a. long-term contact b. combined elements c. amount of corrosion d. amount of nickel used

of the alloy.

ANS: C

A B C D

Feedback All permanent restorations have long-term contact with oral structures. The combination of elements is only significant if corrosion occurs. Biocompatibility of dental alloys is related primarily to their corrosion. Approximately 15% of the population is allergic to nickel.

DIF: Knowledge REF: p. 152 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. Solder metals usually rely on a. tin b. nickel

to encourage a lower melting temperature of the solder.

c. copper d. titanium ANS: A

A B C D

Feedback These alloys contain special elements, such as tin, to encourage a lower melting rate. Nickel is a base metal that can cause allergic reactions. Copper adds strength. Titanium is not used in solder.

DIF: Knowledge REF: p. 152 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. People are most likely to have an allergic reaction to which of the following base metals used

in dentistry? a. Tin b. Nickel c. Copper d. Titanium e. Chromium

ANS: B

A B C D E

Feedback Tin has high biocompatibility. About 10% to 15% of individuals exhibit nickel hypersensitivity, far above the prevalence for any other metal. Copper has high biocompatibility. Titanium has high biocompatibility. Chromium has high biocompatibility.

than alloy metals. Some alloys are formed into restorations by casting. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C

Feedback Statement 1 is incorrect; statement 2 is correct. AeNnK Statement 1 is incorreT ctE; S stT atB em t 2SE is L coLrE reR ct. . COM Alloys have physical and chemical properties more appropriate to dental applications than pure metals. Some alloys are formed into restorations by casting. Statement 1 is incorrect; statement 2 is correct.

DIF: Comprehension REF: p. 138 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. Which of the following is not considered a noble metal in dentistry? a. Gold b. Silver c. Platinum d. Palladium ANS: B

A B

Feedback Gold is considered a noble metal in dentistry. There are seven noble metals in the periodic table, but only three are common in dental casting alloys: gold (periodic table symbol Au), palladium (Pd), and platinum (Pt). Some metallurgists also consider silver (Ag) a noble metal, but

C D

because of its tendency to corrode in the harsh oral environment, silver is not considered a noble metal in dentistry. Platinum is considered a noble metal in dentistry. Palladium is considered a noble metal in dentistry.

A B C D

Feedback Silver alloys that spark a reaction usually contain nickel. Patients who are allergic to nickel are 39% more likely to be allergic to cobalt as well. Patients who are allergic to cobalt may be allergic to chromium. Patients who are allergic to cobalt may be allergic to aluminum.

DIF: Knowledge REF: p. 152 OBJ: 6 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 29. Dental alloys have a crystal structure like ice, salt, or sugar. These crystals, or

as they

are called in metallurgy, can be seen clearly under a microscope. a. gradations b. granules c. lattice d. grains ANS: D

A B C D

Feedback Gradations are changes taking place through a series of stages. Granules are typically larger in size. Lattice is part of the crystal structure. These crystals, or grains as they are called in metallurgy, can be seen clearly under a microscope.

30. The color of an alloy is a good predictor of its composition or other properties. Yellow alloys

contain gold. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

Feedback The color of an alloy is not a good predictor of its composition or other properties. Yellow and white alloys may contain gold or not; it is impossible to tell from the color. The color of an alloy is not a good predictor of its composition or other properties. Yellow and white alloys may contain gold or not; it is impossible to tell from the color. The color of an alloy is not a good predictor of its composition or other properties. Yellow and white alloys may contain gold or not; it is impossible to tell from the color. The color of an alloy is not a good predictor of its composition or other properties. Yellow and white alloys may contain gold or not; it is impossible to tell from the color.

DIF: Comprehension REF: p. 142 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 ProvidiT ngESSuT ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General 31. The a. flow b. liquidus c. solidus d. viscosity

is the temperature at which an alloy melts completely.

ANS: B

A B C D

Feedback Flow is the ability to run smoothly. Solidus is the temperature at which the entire alloy freezes on cooling. The temperature at which the entire alloy melts on heating is called the liquidus. Viscosity is the thickness of the material.

DIF: Knowledge REF: p. 143 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. The a. flow b. liquidus

is the temperature at which the entire alloy freezes on cooling.

c. solidus d. viscosity ANS: C

A B C D

Feedback Flow is the ability to run smoothly. Liquidus is the temperature at which the entire alloy melts. The temperature at which the entire alloy freezes on cooling is the solidus. Viscosity is the thickness of the material.

and bond to the alloy at a temperature below the solidus.

ANS: B

A B C D

Feedback Liquefy means to become a liquid. The ceramic must sinter and bond to the alloy at a temperature below the solidus. Melt is to become liquid by heat. Flow is to be able to move.

A B C D

Feedback Area is determined as the length times the width. The density of an alloy is the mass in grams that occupies a volume of one cubic centimeter. Thickness is the depth of the material. Circumference is the length around a circle.

and cost

in any given

volume of restoration. a. grams; less; dose b. mass; more; mass c. mass; less; dose d. grams; less; mass ANS: B

A B C D

Feedback Because alloys are sold by mass, high-density alloys cost more because more mass is present in any given volume of restoration. Because alloys are sold by mass, high-density alloys cost more because more mass is present in any given volume of restoration. Because alloys are sold by mass, high-density alloys cost more because more mass is present in any given volume of restoration. Because alloys are sold by mass, high-density alloys cost more because more mass is present in any given volume of restoration.

DIF: Comprehension REF: p. 143 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. Which of the following is not an organization that classifies and certifies alloys? a. American Dental Association b. French Institute of Dental Materials c. International Standards Organization d. All of the above e. Only A and C ANS: E

A B C D E

Feedback A and C are correct. A and C are correct. The correct entity is the Nordic Institute of Dental Materials. A and C are correct. Only A and C are correct. Three major organizations currently classify and certify alloys: the American Dental Association (ADA), the Nordic (Scandinavian) Institute of Dental Materials (NIDM), and the International Standards Organization (ISO).

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 37. Noble alloys must have at least 15% noble metal content. Noble content must include gold to

be classified. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: D

A B C D

Feedback Statement 1 is incorrect; statement 2 is incorrect. Statement 1 is incorrect; statement 2 is incorrect. Statement 1 is incorrect; statement 2 is incorrect. Noble alloys must have at least 25% noble metal content but have no stipulation for gold content.

DIF: Comprehension REF: p. 145 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. The color of oxides on metal varies from

on high-noble alloys and some noble alloys to oxides on some base-metal alloys. a. dark gray; dark yellow b. light yellow; light graylight yellow; dark gray dc. dark gray; light yellow ANS: C

A B C D

Feedback The color of oxides varies from light yellow on high-noble alloys and some noble alloys to dark gray or even black oxides on some base-metal alloys. The color of oxides varies from light yellow on high-noble alloys and some noble alloys to dark gray or even black oxides on some base-metal alloys. The color of oxides varies from light yellow on high-noble alloys and some noble alloys to dark gray or even black oxides on some base-metal alloys. The color of oxides varies from light yellow on high-noble alloys and some noble alloys to dark gray or even black oxides on some base-metal alloys.

DIF: Comprehension REF: p. 149 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39. The color of oxides on metal varies from

on high-noble alloys and some noble alloys to oxides on some base-metal alloys. a. dark gray; dark yellow b. light yellow; light gray

c. light yellow; dark gray d. dark gray; light yellow ANS: C

A B C D

A B C

Feedback High-noble alloys have a melting point of 1554° and 1772° C, depending on other added metals. Noble metals such as gold alloy have a melting temperature of 1064° C. Base metals are difficult to cast and polish.

DIF: Comprehension REF: p. 140 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Why are elements such as iron, gallium, iridium and tin added to the metal bases for a

ceramic-faced crown? a. Forms a surface oxide layer to bond to b. Smooth surface to prevent irregularities in the ceramic c. Decreases the thickness to allow for more ceramic build-up d. Lowers the solidus of the metal so it is compatible with the ceramic temperatures ANS: A

Feedback Because of the low reactivity of gold, high-noble and some noble alloys do not form a sufficient oxide layer to ensure reliable ceramic bonding. For these alloys, elements such as iron, gallium, indium, or tin must be added in small

quantities to form a surface oxide layer. Because of the low reactivity of gold, high-noble and some noble alloys do not form a sufficient oxide layer to ensure reliable ceramic bonding. For these alloys, elements such as iron, gallium, indium, or tin must be added in small quantities to form a surface oxide layer. Because of the low reactivity of gold, high-noble and some noble alloys do not form a sufficient oxide layer to ensure reliable ceramic bonding. For these alloys, elements such as iron, gallium, indium, or tin must be added in small quantities to form a surface oxide layer. Because of the low reactivity of gold, high-noble and some noble alloys do not form a sufficient oxide layer to ensure reliable ceramic bonding. For these alloys, elements such as iron, gallium, indium, or tin must be added in small quantities to form a surface oxide layer.

DIF: Comprehension REF: p. 147 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast high-noble metals, noble metals, and base metals. ANS:

High-noble: High-noble alloys are expensive because their gold, palladium, or platinum constituents are expensive. The less alloy content, the softer the metal tends to be. Noble: Noble alloys have at least 25% noble metal content but have no stipulation for gold content. The additional content provides a stronger, more durable product. Base: The predominantly base-metal alloys may have minor amounts of noble elements, and their primary constituents are nickel or cobalt. Of all of the dental casting alloys, these alloys are the most complex and contain six to eight elements including molybdenum, chromium, aluminum, vanadium, iron, carbon, beryllium, manganese, gallium, and silicon in addition to the primary elements. As a group, these alloys have extremely high yield strengths and hardness. DIF: Analysis REF: p. 143 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Discuss the process of categorizing casting metals used in dentistry. ANS:

Dental casting alloys (versus wrought alloys) are alloys used clinically in their as-cast form. In dentistry, casting alloys are categorized in several ways but most often on the basis of noble metal content. The nobility of an alloy is expressed as a sum of the weight percentages of the noble metals in the alloy. For example, if an alloy contains 60% gold, 10% palladium, 5% platinum, and 25% copper, the nobility would be 75% (the sum of gold, palladium, and platinum). Alloys also are described on the basis of their most common metal. For example, an alloy with 75% gold often is described as gold based, or an alloy with 60% nickel may be described as nickel based. The term based indicates which metal is the major component in the alloy and should not be confused with the term base metal. There are three major organizations worldwide. The ADA is the entity of choice in the United States. DIF: Analysis REF: p. 144 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to Unlisted topic (metals used in dentistry) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

Chapter 12: Casting, Soldering, and Welding Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Which of the following sequences describing the steps involved in making a dental casting

from start to finish is correct? a. Burnout, casting, making the wax pattern, spruing the pattern, investing, removal of investment, pickling, and finishing b. Making the wax pattern, burnout, casting, spruing the pattern, investing, removal of investment, pickling, and finishing c. Making the wax pattern, spruing the pattern, burnout, casting, investing, removal of investment, pickling, and finishing d. Making the wax pattern, spruing the pattern, investing, burnout, casting, removal of investment, pickling, and finishing ANS: D

A B C D

Feedback Any other sequencing would not be successful. Any other sequencing would not be successful. Any other sequencing would not be successful. The correct sequence is making the wax pattern, spruing the pattern, investing, burnout, casting, removal of investment, pickling, and finishing.

DIF: Analysis REF: TpE . S1T 55BANKS OE BL J:LE 2 R.COM TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. The accuracy of a cast crown may be as good as

% in dimensional change from the wax

pattern if care is taken to perform each step properly. a. 1 b. 0.5 c. 0.1 d. 0.05 e. 0.01 ANS: D

A B C D E

Feedback This would be an inaccurate figure when all parameters are met. This would be an inaccurate figure when all parameters are met. This would be an inaccurate figure when all parameters are met. The accuracy of a cast crown may be as good as 0.05% in dimensional change from the wax pattern if care is taken to perform each step properly. This would be an inaccurate figure when all parameters are met.

DIF: Knowledge

REF: p. 155

OBJ: 1

TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. What is the purpose of the sprue? a. Provides access channel for molten alloy to reach casting b. Form the occlusal surface of a casting c. Form the proximal surface of a casting d. Reduce the metal content of a casting ANS: B

A B C D

Feedback The purpose of the sprue is to form a channel in investment through which the molten alloy travels to form the restoration. The details of the wax pattern of the crown, inlay, or bridge include the occlusal surface of a casting. The details of the wax pattern of the crown, inlay, or bridge include the proximal surface of the casting. The sprue provides an opening in which the molten metal is injected into the casting and will leave additional metal behind.

TESTBANKSELLER.COM

4. To prevent premature freezing in the sprue channel, sprues are generally as

_ in diameter

and as as possible. a. small; long b. small; short c. large; long d. large; short ANS: D

A B C D

Feedback To prevent premature freezing in the sprue channel, sprues are generally as large in diameter and as short as possible. To prevent premature freezing in the sprue channel, sprues are generally as large in diameter and as short as possible. To prevent premature freezing in the sprue channel, sprues are generally as large in diameter and as short as possible. To prevent premature freezing in the sprue channel, sprues are generally as large in diameter and as short as possible.

5. Which of the following statements is(are) true of sprues? a. Sprues may be made of wax, plastic, or metal. b. Sprues are placed on cusps of the wax pattern. c. Sprues are placed in the central groove of the wax pattern. d. A and B are true statements. e. A and C are true statements. ANS: D

A B C D E

Feedback A and B are both correct. A and C are both correct. Sprue placement in the central groove would complicate occlusal adjustment of the crown at cementation. Sprues may be made of wax, plastic, or metal. Sprues are placed on cusps of the wax pattern. A and B are both correct.

DIF: Comprehension REF: p. 158 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. Which of the following statements is true of investments used for casting? a. The refractory material in most dental investments is a form of calcium. b. The binder and the refractory material contribute to expansion of the investment. c. The binder and the refrT acEtoSrT yB mA atNerKiaSl E coLnL trE ibR ut.eCtoOcMontraction of the investment. d. The binder, but not the refractory material, contributes to expansion of the

investment. e. The refractory material, but not the binder, contributes to expansion of the

investment. ANS: D

A B C D E

Feedback The refractory material is silica. The binder and the refractory material contribute to expansion of the investment. The material should not contract or the end product will not fit. The refractory material does contribute to the expansion of the material. The binder does contribute to the expansion of the material.

DIF: Comprehension REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. Which of the following is correct about phosphate-bonded investments? a. Use a silica refractory b. Use a gypsum investment binder c. Are used for ceramic–alloy restorations

d. Both A and C e. Both B and C ANS: E

A B C D E

Feedback Gypsum investment binder is not used in this situation. A and C are both correct. A and C are both correct. A and C are both correct. Phosphate-bonded investments use silica refractory and are used for ceramic– alloy restorations and many partial denture frameworks; however, theyuse ammonium phosphate–magnesia binder rather than gypsum investment binder.

DIF: Comprehension REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. What is the purpose of a casting ring? a. Retains the investment while it sets b. Is commonly lined with a dry ceramic-paper liner c. Is commonly lined with a wet ceramic-paper liner d. Both A and B e. Both A and C ANS: E

A B C D E

Feedback A and C are both correct. The ring is commonly lined with a wet ceramic-paper liner to prevent the liner from absorbing water from the investment. A and C are both correct. A and C are both correct. A casting ring retains the investment while it sets. It is commonly lined with a wet ceramic-paper liner.

DIF: Comprehension REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. The investment material is a. hydrophilic; hydrophilic b. hydrophilic; hydrophobic c. hydrophobic; hydrophilic d. hydrophobic; hydrophobic ANS: B

; the wax pattern is

A B C D

Feedback This mismatch makes the formation of bubbles or voids a problem during investing. An investment material is hydrophilic, and a wax pattern is hydrophobic. This mismatch makes the formation of bubbles or voids a problem during investing. This mismatch makes the formation of bubbles or voids a problem during investing.

DIF: Knowledge REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. Why is a surfactant used prior to investment? a. Wet the ceramic-paper liner b. Liquefy the investment material c. Reduce residual stress in the wax pattern d. Aid the flow of the investment material over the wax pattern ANS: D

A B C D

Feedback Water is used to wet the liner. Investment material is mixed to a specific ratio of material and water. Surfactant will not remove stresses from the wax pattern. Before investing, surfT acEtaSnT tB mA ayNbKeSuE seLdLtoEaRid.C thO eM flow of the investment material over the wax pattern. The surfactant lowers the contact angle of the aqueous investment on the hydrophobic wax.

DIF: Knowledge REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. An invested wax pattern should set for at least a. 10 minutes b. 45 minutes c. 12 hours d. 24 hours e. 1 week

before burnout.

ANS: B

A B C D

Feedback Ten minutes would not allow the investment to set up completely. The invested wax pattern is allowed to set for at least 45 minutes but should not be allowed to desiccate. This time is too long. Material begins to desiccate after 45 minutes. This time is too long. Material begins to desiccate after 45 minutes.

This time is too long. Material begins to desiccate after 45 minutes.

material? a. Expansion of the investment from added water is called hydroscopic expansion. b. Investments are designed to expand to compensate for casting shrinkage. c. Expansion of the investment from heat is called thermal expansion. d. A, B, and C are true statements. e. B and C are true statements. ANS: D

A B C D E

Feedback Expansion of the investment from added water is called hygroscopic expansion. B and C are correct. B and C are correct. B and C are correct. Investments are designed to expand to compensate for casting shrinkage; and expansion of the investment from heat is called thermal expansion.

DIF: Knowledge REF: p. 160 OBJ: 6 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. The total expansion of the investment is the sum of the hygroscopic and thermal expansions.

Investments rely primarily on hygroscopic expansion to compensate for casting shrinkage of the metal. a. The first statement is correct; the second statement is correct. b. The first statement is correct; the second statement is incorrect. c. The first statement is incorrect; the second statement is correct. d. The first statement is incorrect; the second statement is incorrect. ANS: C

A B C

Feedback The first statement is correct; the second statement is incorrect. The first statement is correct; the second statement is incorrect. The total expansion of the investment is the sum of the hygroscopic and thermal expansions; however, today’s investments rely primarily on thermal expansion to compensate for casting shrinkage of the metal. The first statement is correct; the second statement is incorrect.

DIF: Comprehension REF: p. 160 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of

laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 14. What regulates the amount of thermal expansion of the investment? a. Temperature used during burnout b. Type of silica refractory used c. Type of inlay wax used d. A and B e. B and C ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. The wax is generally not a factor, because it is burned away before the thermal expansion occurs. The amount of thermal expansion of the investment is regulated by the type of silica refractory used and the temperature used during burnout. A and B are both correct.

DIF: Knowledge REF: p. 160 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. If molten alloy was cast into a ring at room temperature, what will occur? a. Casting would be much larger than the die. b. Margins of the casting would be complete. c. Investment would partially decompose. d. Investment would likely crack. ANS: C

A B C D

Feedback The casting is a result of the size of the die. The molten metal would likely solidify prematurely. The investment would likely crack, not decompose. If molten alloy were cast into a casting ring at room temperature, the investment would likely crack.

, the required temperature of a burnout oven for proper casting will vary. a. type of investment b. liquidus of the alloy to be cast c. solidus of the alloy to be cast

d. A, B, and C are all correct. e. Only A and B are correct. ANS: E

A B C D E

Feedback A and B are correct. Only A and B are correct. Solidus does not factor into this scenario. Only A and B are correct. The temperature in the burnout oven will vary, depending upon the type of investment, the liquidus of the alloy, and the composition of the alloy.

DIF: Comprehension REF: p. 161 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. Following removal of a ring from the burnout oven, any delay in casting of more than a. b. c. d. e.

will severely compromise the fit and quality of the cast restoration. 1 to 2 seconds 8 to 10 seconds 20 to 30 seconds 60 to 90 seconds 2 to 3 minutes

ANS: C

A B C

D E

Feedback This time is well within the casting window. This time is well within the casting window. Following removal from the burnout oven, the ring must be cast as soon as possible, and any delay of more than 20 to 30 seconds will severely compromise the fit and quality of the cast restoration. This time is beyond the casting window, and the mold and material would be at significantly different temperatures. This time is beyond the casting window, and the mold and material would be at significantly different temperatures.

DIF: Knowledge REF: p. 161 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. The temperature in a burnout oven is commonly a. 100° C b. 100° F c. 500° C d. 500° F ANS: C

for high noble alloys.

A B C D

Feedback This temperature is too low to be compatible with the molten metal. This temperature is too low to be compatible with the molten metal. The temperature in a burnout oven is commonly 500° C for high noble alloys. This temperature is too low to be compatible with the molten metal.

DIF: Knowledge REF: p. 161 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. What method is used to inject the molten alloy into the casting ring? a. Slip casting b. Press molding c. Linear casting machine d. Centrifugal casting machine ANS: D

A B C D

Feedback Slip casting is used with ceramics. Most casting is done in a centrifugal casting machine. Alloys may be heated with a torch or electronic induction with this technique. Linear casting is another investment casting method. Most casting is done in a centrifugal casting machine. Alloys may be heated with a torch or electronic inTdEuS ctT ioB nAwNitK hS thEisLtL ecEhR ni. quCeO .M

DIF: Knowledge REF: p. 161 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. A casting alloy is heated in a a. burnout oven b. casting ring c. sprue base d. crucible

made of heat-resistant ceramic.

ANS: D

A B C D

Feedback Burnout ovens heat the investment and burn out the wax pattern. Casting rings are metal and hold the investment and wax pattern in place for burnout and casting. Sprue base is the access opening for the molten metal. The casting alloy is heated in a crucible made of heat-resistant ceramic.

DIF: Knowledge REF: p. 161 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of

laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Which factor below does not determine the type of flux used during dental castings? a. Type of heat source used to melt the alloy b. Liquidus of the casting alloy c. Type of casting alloy d. Type of investment e. Type of wax ANS: E

A B C D E

Feedback All of the choices are true except the type of wax, because it has been burned out before casting the molten alloy. All of the choices are true except the type of wax, because it has been burned out before casting the molten alloy. All of the choices are true except the type of wax, because it has been burned out before casting the molten alloy. All of the choices are true except the type of wax, because it has been burned out before casting the molten alloy. The type of flux used for casting depends upon the liquidus of the casting alloy, the type of heat source used, the type of casting alloy, and the type of investment.

DIF: Knowledge REF: p. 161 OBJ: 8 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Which characteristics are necessary for a blowtorch to heat casting alloys? a. May operate on a combination of natural gas and compressed air for b. c. d. e.

low-temperature alloys May operate on a combination of natural gas and oxygen for higher temperature alloys Must heat the alloy sufficiently to ensure a low viscosity of the alloy for casting A, B, and C A and C

ANS: D

A B C D

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. The blowtorch used to heat casting alloys may operate on a combination of natural gas and compressed air for low-temperature alloys or may operate on a combination of natural gas and oxygen for higher temperature alloys. The blowtorch must heat the metal sufficiently, or it will be too viscous to flow into all of the finest details in the investment.

A, B, and C are all correct.

DIF: Comprehension REF: p. 162 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. For some gold-based alloys, bench cooling produces a

_ state of the alloy

referred to as a(n) . a. harder; weaker; ordered solution b. harder; stronger; ordered solution c. softer; weaker; eutectic d. softer; stronger; eutectic ANS: B

A B

C D

Feedback The end state of the casting is stronger. For some gold-based alloys, bench cooling produces a harder, stronger state of the alloy. The improvement in properties results from the formation of an ordered solution. A softer product is the result of quenching the casting immediately in a water bath. A softer product is the result of quenching the casting immediately in a water bath.

EF p.R. 16C3OM OBJ: 9 DIF: Comprehension TESTBANKSRE L:LE TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. Which term refers to rapidly cooling a casting in cold water? a. Brazing b. Pickling c. Quenching d. Bench cooling ANS: C

A B C D

Feedback Brazing is a metal joining process. Pickling is an acid bath. Rapidly cooling a casting in cold water is called quenching. Bench cooling is a slow process.

a. b. c. d. e.

Uses hot calcium carbonate Removes surface oxides Uses hot sulfuric acid A and B B and C

ANS: E

A B C D E

Feedback Pickling uses a hot acid bath. B and C are both correct. Band C are both correct. B and C are both correct. Pickling a casting removes dark surface oxides. It uses hot sulfuric acid. Not all alloys may be treated in this manner; the technique is used primarily for high-gold alloys.

DIF: Comprehension REF: p. 163 OBJ: 9 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. The investment used in casting is ; the wax pattern is a. hydrophobic; hydrophobic b. hydrophobic; hydrophilic c. hydrophilic; hydrophilic d. hydrophilic; hydrophobTiE c STBANKSELLER.COM

ANS: D

Feedback Before investing, the wax pattern may be treated with a surfactant that aids flow of the water-based (hydrophilic) investment material over the water-hating (hydrophobic) wax pattern. Before investing, the wax pattern may be treated with a surfactant that aids flow of the water-based (hydrophilic) investment material over the water-hating (hydrophobic) wax pattern. Before investing, the wax pattern may be treated with a surfactant that aids flow of the water-based (hydrophilic) investment material over the water-hating (hydrophobic) wax pattern. Before investing, the wax pattern may be treated with a surfactant that aids flow of the water-based (hydrophilic) investment material over the water-hating (hydrophobic) wax pattern.

DIF: Comprehension REF: p. 159 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. Investment is retained in a

while it sets.

a. b. c. d.

mold crucible centrifuge casting ring

ANS: D

A B C D

Feedback In dental casting, a mold is made of wax. A crucible is used to melt the casting metal. A centrifuge is used to spin the metal into the burned-out investment. To retain the investment while it sets, a casting ring is placed onto the sprue base.

DIF: Knowledge REF: p. 158 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. Because cast metal a. shrinks; shrinks b. expands; shrinks c. shrinks; expands d. expand; expands

as it freezes, investment must

as it sets.

ANS: C

A B C D

Feedback If cast metal shrinks as it freezes, it is essential the investment expands to compensate. If cast metal shrinks as it freezes, it is essential the investment expands to compensate. If cast metal shrinks as it freezes, it is essential the investment expands to compensate. If cast metal shrinks as it freezes, it is essential the investment expands to compensate.

DIF: Comprehension REF: p. 160 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 29. Expansion of the binder from added water to the investment is called a. hygroscopic b. chemical c. burnout d. thermal ANS: A

Feedback

expansion.

B C D

Expansion of the binder from added water (from the addition of the water after the original water is added for mixing but before the investment sets) is called hygroscopic expansion. The process is not a chemical reaction. Burnout is the process of melting the wax out of the mold. Thermal refers to the investment’s response to temperature.

than the

burned out investment. a. 500° F higher b. 500° C higher c. 500° F lower d. 500° C lower ANS: B

A B C D

Feedback This temperature would not be hot enough. A rule of thumb is that the melting temperature (liquidus) of the alloy should not be more than 500 C higher than the burnout temperature. This temperature would not be hot enough. This temperature wouTldEnSoT tB beAhNoK t eSnE ouLgLhE . R.COM

DIF: Knowledge REF: p. 161 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 31. Which of the following will flux minimize? a. Oxidation b. Melting time c. Freezing time d. Melting temperature ANS: B

A B C D

Feedback A flux is usually added to minimize the formation of oxides that impair the heating and casting of the alloy and decrease the final quality of the casting. Melting time and temperature will depend on the type of alloy being used. Freeze of material will occur as the heat dissipates from the casting once it is allowed to rest. Melting time and temperature will depend on the type of alloy being used.

DIF: Knowledge REF: p. 164 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. What will occur if the molten metal and the investment material are too far apart in

temperature? a. The metal will solidify too quickly. b. There will be too much shrinkage. c. The investment will crack. d. The metal will crack. ANS: C

A B C D

Feedback Metal that is not heated to the proper temperature will be too viscous to flow. Investment material expands. The thermal expansion of the investment is not reversible, and if the ring cools before it is cast, either the investment will crack or the casting will be distorted. The metal would distort.

A blowtorch A casting oven An electric current Only A and B are correct. Only A and C are correct.

ANS: E

A B C D E

Feedback A and C are both correct. A and C are both correct. A casting oven is used to burn out the wax pattern from the investment. Only A and B are correct. Casting alloys may be heated by blowtorch or electric current.

DIF: Comprehension REF: p. 161 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. What will occur if base-metal castings are pickled? a. Tarnish b. Oxidation c. Corrosion

d. Crystallization ANS: B

A B C D

Feedback Tarnish is the result of a chemical reaction with certain alloys. Pickling removes oxidation from high-gold metals. High-gold alloys are pickled, but acidic treatment of predominantly base-metal alloys will significantly corrode and damage them. Base metals do not crystallize.

disk.

ANS: C

A B C D

Feedback A cuttle disk is not abrasive or sturdy enough to remove a sprue. A carbide disk could damage the casting therefore care must be taken not to scar the restoration with thTeEdS isT kB inAthNiK sS steEpL. LER.COM A diamond disk could damage the casting; therefore care must be taken not to scar the restoration with the disk in this step. The sprue is removed with a thin carborundum disk on a handpiece.

DIF: Knowledge REF: p. 163 OBJ: 9 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. Which is the correct order of operations to construct a cast appliance? a. Wax pattern, investment, sprue, burnout, cast b. Investment, wax pattern, sprue, cast, burnout c. Wax pattern, sprue, cast, burnout, investment d. Wax pattern, sprue, investment, burnout, cast ANS: D

A B C D

Feedback This order of operations would not result in a successful restoration. This order of operations would not result in a successful restoration. This order of operations would not result in a successful restoration. The correct order of operations to construct a cast appliance is to wax the pattern, place a sprue, invest the pattern, burn out in an oven, and cast the

appliance. DIF: Analysis REF: p. 155 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 37. Most dental solders are silver or gold alloys. Only certain types of alloy solders require flux. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B C D

Feedback Statement 1 is correct; statement 2 is incorrect. All solders require the use of flux. Statement 1 is correct; statement 2 is incorrect. All solders require the use of flux. Statement 1 is correct; statement 2 is incorrect. All solders require the use of flux. Statement 1 is correct; statement 2 is incorrect. All solders require the use of flux.

DIF: Comprehension REF: p. 163 OBJ: 10 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP r oc ed u re s B, Demonstrate an understanding of LLER.COM laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. Which of the following is an advantage to using wax when constructing an indirect

restoration? a. Flows easily b. Releases stress c. Does not distort d. May be formed on the tooth ANS: D

A B C D

Feedback The wax flows easily; therefore it may not remain stable when off of the die. A wax pattern will release stress when on the die, which could crack the wax. A wax pattern will distort in 1 to 2 minutes. Although time consuming, smaller wax patterns may be formed directly on the tooth.

DIF: Knowledge REF: p. 156 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

39. During the casting process, how is a metal sprue treated? a. Coated with a surfactant b. Removed before casting c. Burned out with the wax d. Secured in the investment ANS: B

A B C D

Feedback The wax pattern is sprayed with a surfactant to accept the hydrophilic investment. If metal, the sprue must be removed before casting, because the metal will not burn out. The metal sprue will not burn out. The sprue does not need to be secured.

DIF: Knowledge REF: p. 158 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. Once a molten alloy freezes, what is the percentage of shrinkage that may occur? a. 0.5% to 1.0% b. 1.0% to 2.5% c. 1.5% to 2.0% d. 1.2% to 2.5% ANS: B

A B C D

Feedback Depending on the alloy, the molten alloy shrinks 1.0% to 2.5% as it freezes. Depending on the alloy, the molten alloy shrinks 1.0% to 2.5% as it freezes. Depending on the alloy, the molten alloy shrinks 1.0% to 2.5% as it freezes. Depending on the alloy, the molten alloy shrinks 1.0% to 2.5% as it freezes.

DIF: Knowledge REF: p. 158 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Approximately how long does it take for the wax to burn out in the kiln? a. 30 minutes b. 1 hour c. 1.5 hours d. 2 hours ANS: B

A B

Feedback It takes about 1 hour in the kiln, at full temperature, for wax to burn out. It takes about 1 hour in the kiln, at full temperature, for wax to burn out.

C D

It takes about 1 hour in the kiln, at full temperature, for wax to burn out. It takes about 1 hour in the kiln, at full temperature, for wax to burn out.

DIF: Knowledge REF: p. 163 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast casting with milling. ANS:

Casting is a process by which a detailed wax pattern of a dental restoration is converted into alloy or ceramic. The casting process allows the dentist and dental laboratory to custom-make precision restorations for missing or damaged teeth. Casting is a multi-step process that requires at least 2 appointments to complete. Milling of restorations, where a block of alloy or ceramic is cut back to a final restorative shape by a precision machine (usually computer-directed), is growing in use, particularly for ceramic restorations. The preparation is scanned using a CAD/CAM computer program and the preparation, construction, and cementation take place in one appointment. DIF: Analysis REF: p. 157 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Explain the advantages and disadvantages of using inlay wax to construct an indirect

restoration. ANS:

Wax is used because it is easy to manipulate, inexpensive, and well suited to making custom restorations. Wax also is easy to completely eliminate after investing. Although wax is a convenient material for making a pattern of the dental restoration, it also has a tendency to flow, release stress, and expand or contract with changes in temperature. The waxing process itself does not oversize or undersize the dimensions of a restoration, but distortion of the wax pattern is a serious risk. DIF: Comprehension REF: p. 156 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (wrought metals and soldering) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

Chapter 13: Polymers in Prosthodontics Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. Which term is used to describe the extent to which all monomer is polymerized in a polymer? a. Modulus of elasticity b. Degree of conversion c. Threshold level d. Bond strength ANS: B

A B C D

Feedback Modulus of elasticity is the object’s or substance’s tendency to be deformed elastically. The extent to which all monomer is polymerized in a polymer is referred to as degree of conversion. Threshold level is the level that is just barely perceptible. Bond strength is the strength with which a chemical bond holds two atoms together.

DIF: Knowledge REF: p. 170 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 ProvidiT ngESSuT ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General 2. Which of the following statements is true of the process of polymerization? a. Polymerization is a chemical reaction that links small inorganic compounds called

monomers into long chains of repeating monomer subunits. b. Polymers that form by simple addition may not shrink as much as those that form

by condensation. c. Polymers with high degrees of conversion have high levels of residual monomer. d. Most prosthodontic polymers expand significantly as polymerization proceeds. ANS: B

A B C D

Feedback Polymerization is a chemical reaction that links small organic compounds called monomers into long chains of repeating monomer subunits. Most prosthodontic polymers shrink significantly as polymerization proceeds. Polymers with high degrees of conversion often have low levels of residual monomer. Polymers that form by simple addition may not shrink as much as those that form by condensation.

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. High degrees of polymerization lead to a. more; more b. less; less c. more; less d. less; more

rigid,

soluble polymer networks.

ANS: D

A B C D

Feedback High degrees of polymerization lead to more rigid, less soluble polymer networks. High degrees of polymerization lead to more rigid, less soluble polymer networks. High degrees of polymerization lead to more rigid, less soluble polymer networks. Low degrees of polymerization would lead to less rigid, more soluble polymer networks.

DIF: Comprehension REF: p. 171 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. Which of the following is the most common type of chemical reaction used to form polymers

used for dental restorationsT?ESTBANKSELLER.COM a. Condensation to form epoxy polymers b. Ring opening to form epoxy polymers c. Ring opening to form silicone polymers d. Condensation to form silicone polymers e. Free-radical addition to form acrylic polymers ANS: E

A B C D E

Feedback Epoxy polymers are light cured. Silicone polymers are used as soft liner materials. Silicone polymers are used as soft liner materials. Epoxy polymers are light cured. The free-radical addition reaction is the most common type of chemical reaction used to form polymers for dental restorations.

DIF: Knowledge REF: p. 171 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. Which of the following is the most common monomer found in acrylic polymers used in

dentistry? a. Hydroxyethyl methacrylate

b. c. d. e.

Poly(methyl methacrylate) Methyl methacrylate Butyl methacrylate Octyl methacrylate

ANS: C

A B C D E

Feedback Hydroxyethyl methacrylate increases the degree of wetting. Poly(methyl methacrylate) is a transparent thermoplastic. Methyl methacrylate is the most common monomer found in acrylics used in dentistry. Butyl methacrylate is another monomer used in dentistry, but it is not as common. Octyl methacrylate contains strong oxidizing acids.

DIF: Knowledge REF: p. 169 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. The polymerization reaction shrinkage of acrylics approaches a. 1 b. 3 c. 6 d. 12

vol %.

ANS: C

A B C D

Feedback This is a percent lower than research has determined to be accurate. This is a percent lower than research has determined to be accurate. The polymerization reaction shrinkage of acrylics approaches 6% by volume. This is a percent significantly higher than acceptable levels of shrinkage.

DIF: Knowledge REF: p. 172 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. Cross-linked acrylic polymers are a. less rigid b. more soluble c. more temperature resistant d. A, B, and C e. A and C ANS: C

Feedback Cross-linked polymers are more rigid.

than their non-cross-linked counterparts.

B C D E

Cross-linked polymers are less soluble. Cross-linked acrylic polymers are more rigid, more temperature resistant, and less soluble than their non-cross-linked counterparts. C is the correct answer. C is the correct answer.

DIF: Comprehension REF: p. 172 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. What do chemicals such as dibutyl phthalate cause a poly(methyl methacrylate) to become? a. Stiff b. Porous c. Greasy d. Rubbery e. Slippery ANS: D

A B C D E

Feedback Dibutyl phthalate is a plasticizer that helps the material become rubbery, not stiff. It does not impact the porosity of the finished product. Dibutyl phthalate is not a lubricant. Chemicals such as dibutyl phthalate will cause a poly(methyl methacrylate) to become rubbery. Dibutyl phthalate is not a lubricant.

DIF: Knowledge REF: p. 173 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. During denture fabrication, a custom impression tray is typically used to obtain a final

impression during the a. first b. second c. third d. fourth e. fifth

appointment.

ANS: B

A B C D

Feedback Diagnostic study models are obtained at the first appointment. A custom impression tray is used to obtain the final impression during the second appointment. Record bases are made and a wax rim added at the third appointment. Master casts are mounted and denture teeth are chosen for try-in at the fourth

appointment. Dentures are delivered at the fifth appointment.

DIF: Knowledge REF: p. 174 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to 1. fabricate custom impression trays MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. The denture base resin mixture should be a. sticky b. grainy c. doughy d. rubbery

when it is used to pack the denture flask.

ANS: C

A B C D

Feedback Sticky material is not ready to be used. Grainy material has not been mixed thoroughly. The denture base resin mixture should be doughy when it is used to pack the denture flask. Rubbery material is polymerized past the doughy stage and is no longer viable.

DIF: Knowledge REF: p. 177 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General TESSupp TBorAtiN 11. Which of the following is correct about acrylic polymers used for most dentures? a. Are low in strength b. Have a low modulus of elasticity c. Have a high modulus of elasticity d. A and B e. A and C ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. Modulus of elasticity is low. A and B are both correct. Acrylic polymers used for most dentures are low in strength and have a low modulus of elasticity.

DIF: Knowledge REF: p. 178 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

12. Which of the following statements is true concerning denture acrylic polymers and water

sorption? a. Denture acrylic polymers have low water sorption. b. Months are necessary for full water sorption to occur. c. Water sorption causes denture expansion of as much as 10%. d. Sorption-mediated expansion compensates to some degree for polymerization shrinkage. ANS: C

A B C D

Feedback Denture acrylic polymers have high water sorption. Hours to days are necessary for full water sorption to occur. Sorption-mediated expansion compensates to some degree for polymerization shrinkage. Water sorption causes denture expansion of as much as 2%.

salivary viscosity leads to impaired retention of the denture. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrecT t;EstSatTem enNt K 2S coErL reL ctE . R.COM BA d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

DIF: Knowledge REF: p. 180 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 14. Which statement(s) is(are) correct when contrasting chemical-cured and heat-cured polymers? a. Residual monomer levels are lower in chemical-cured acrylic polymers. b. The clinical fit of heat-cured dentures is somewhat superior to those cured

chemically. c. Both heat- and chemical-cured acrylic polymers have residual stresses that result

from polymerization shrinkage. d. A, B, and C e. A and C

ANS: D

A B C D E

Feedback When contrasting chemical-cured and heat-cured polymers, residual monomer levels are higher in chemical-cured acrylic polymers. The clinical fit of heat-cured dentures is somewhat inferior to those cured chemically. Both heat- and chemical-cured acrylic polymers have residual stresses that result from polymerization shrinkage. C is the correct answer. C is the correct answer.

DIF: Comprehension REF: p. 180 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. How should dentures be cared for when removed from the mouth? a. Stored in water b. Stored in rubbing alcohol c. Boiled and then air dried to kill bacteria and fungi d. Desiccated with acetone to prevent ingress of bacteria ANS: B

A B C D

Feedback When removed from T thE eS mT ouBtA h,NdK enStuErL esLaEreRb.eC stOsM tored in water. Alcohol should not be used with oral appliances. Denture materials would distort if placed in hot water. Acetone should not be used with oral appliances.

DIF: Knowledge REF: p. 181 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 16. Which of the following statement(s) is(are) true of denture soft liners? a. They may be used for patients with severe undercuts of the edentulous ridges. b. Silicone liners harden as time passes, because they contain plasticizer. c. The hardness of the long-term acrylic materials increases slowly as the plasticizer

is leached out by exposure to oral fluids. d. A, B, and C are true statements. e. A and C are true statements. ANS: D

A B C

Feedback They may be used for patients with severe undercuts of the edentulous ridges. Silicone liners do not harden as time passes, because they contain no plasticizer. The hardness of the long-term acrylic materials increases slowly as the

D E

plasticizer is leached out by exposure to oral fluids. A and C are correct. A and C are correct.

DIF: Comprehension REF: p. 182 OBJ: 9 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. What do short-term lining materials consist of? a. Silicone-based polymers b. Methacrylate-based polymers c. Butadiene-styrene rubber-reinforced polymers d. Polyethylene methacrylate powder and liquid plasticizers ANS: D

A B C D

Feedback Silicone-based polymers are used for denture bases. Methacrylate-based polymers are used for denture bases. Butadiene-styrene rubber-reinforced polymers are less frequently used material for dentures. Short-term lining materials consist of polyethylene methacrylate powder and liquid plasticizers.

DIF: Analysis REF: p. 184 OBJ: 9 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO AM , Describe how to prepare, mix, deliver, LrL and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. During fabrication of removable partial dentures, the acrylic bonds

to the

denture teeth and to the alloy framework. a. chemically; chemically b. chemically; mechanically c. mechanically; mechanically d. mechanically; chemically ANS: C

A B C D

Feedback Acrylic bonds to like materials such as teeth. Mechanical retention is used to connect the acrylic to metal. During fabrication of removable partial dentures, the acrylic bonds chemically to the denture teeth and mechanically to the alloy framework. Acrylic bonds to like materials such as teeth. Mechanical retention is used to connect the acrylic to metal. Acrylic bonds to like materials such as teeth. Mechanical retention is used to connect the acrylic to metal.

DIF: Comprehension

REF: p. 184

OBJ: 10

TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. Removable partial dentures use a. unfilled; non-cross b. filled; non-cross c. unfilled; cross d. filled; cross

-linked poly(methyl methacrylate) homopolymer.

ANS: A

A B C D

Feedback Removable partial dentures use unfilled, non-cross-linked poly(methyl methacrylate) homopolymers. Partial dentures are made from the same acrylic materials as complete dentures. Partial dentures are made from the same acrylic materials as complete dentures. Partial dentures are made from the same acrylic materials as complete dentures.

DIF: Knowledge REF: p. 185 OBJ: 10 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Orthodontic appliances use a. unfilled; non-cross b. unfilled; cross c. filled; non-cross d. filled; cross

-linked poly(methyl methacrylate) homopolymer.

ANS: A

A B C D

Feedback Orthodontic appliances use unfilled, non-cross-linked poly(methyl methacrylate) homopolymer. Orthodontic appliances are made from the same acrylic materials as complete dentures. Orthodontic appliances are made from the same acrylic materials as complete dentures. Orthodontic appliances are made from the same acrylic materials as complete dentures.

DIF: Knowledge REF: p. 174 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Why are denture teeth made of acrylic and modified acrylic polymers replacing ceramic

denture teeth? a. Do not wear natural opposing teeth b. Mechanically bond to the acrylic denture base

c. Better absorb occlusal forces and preserve the edentulous ridge d. A, B, and C e. A and C ANS: E

A B C D E

Feedback A and C are correct. Denture teeth chemically bond to the acrylic base. A and C are correct. Only A and C are correct. Denture teeth made of acrylic and modified acrylic polymers have replaced ceramic teeth, because acrylic teeth do not wear natural opposing teeth; they chemically bond to the acrylic denture base; and they better absorb occlusal forces and preserve the edentulous ridge.

DIF: Comprehension REF: p. 185 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Which of the following statement(s) is(are) true regarding acrylic denture teeth? a. The coronal portion of the tooth is constructed of minimally cross-linked polymer

b. c. d. e.

to provide resistance to crazing when the teeth are exposed to solvents during eating. Polymers in the gingival portion of the plastic teeth have maximal cross-linking to ensure the denture baseTcEaS nT boBnA dNtoKtS heEpLoLlyEmRe. rC ofOtM he denture tooth. Cross-linking provides better wear resistance and a more solid feel when the patient chews food. A, B, and C are true statements. A and C are true statements.

ANS: C

A B

C D E

Feedback Polymers in the gingival portion of the plastic teeth have minimal cross-linking to ensure the denture base can bond to the polymer of the denture tooth. The coronal portion of the tooth is constructed of cross-linked polymer to provide resistance to crazing when the teeth are exposed to solvents during eating. Cross-linking provides better wear resistance and a more solid feel when the patient chews food. C is the only correct answer. C is the only correct answer.

DIF: Comprehension REF: p. 187 OBJ: 11 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

23. Which of the following statements is true of Bis-GMA-based polymers used to fabricate

temporary crowns or bridges? a. Lower cost than non-cross-linked acrylic polymers b. May be light-cured, chemical-cured, or dual-cured c. Are more difficult to trim than acrylic polymers d. Do not wear as well as acrylic polymers ANS: B

A B C D

Feedback Bis-GMA-based polymers are more expensive than non-cross-linked acrylic polymers. Bis-GMA-based polymers may be light-cured, chemical-cured, or dual-cured. Bis-GMA-based polymers are easier to trim, particularly at the margins of the restoration. Bis-GMA-based polymers wear better than acrylic polymers.

DIF: Knowledge REF: p. 187 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 24. Custom impression trays are essential for the appropriate construction of a. b. c. d.

prostheses. removable but not fixed fixed but not removable both removable and fixTeE d STBANKSELLER.COM neither removable nor fixed

ANS: C

A B C D

Feedback Custom impression trays are essential for the appropriate construction of both removable and fixed prostheses. Custom impression trays are essential for the appropriate construction of both removable and fixed prostheses. Custom impression trays are essential for the appropriate construction of both removable and fixed prostheses. Custom impression trays are essential for the appropriate construction of both removable and fixed prostheses.

DIF: Knowledge REF: p. 189 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. What advantage(s) do/does light-cured urethane dimethacrylate material have versus

powder-liquid acrylic material? a. Lower polymerization shrinkage b. Quicker fabrication time

c. Lower cost d. A and B e. A and C ANS: E

A B C D

Feedback A and B are both correct. A and B are both correct. Light-cured temporary material is expensive. Advantages of light-cured urethane dimethacrylate material rather than powder-liquid acrylic include low polymerization shrinkage and quicker fabrication time; however, they are substantially more expensive than their acrylic counterparts. Only A and B are correct.

chemically link into long chains of repeating

subunits called . a. monomers; methacrylates b. polymers; methacrylates c. polymers; monomers d. monomers; polymers ANS: D

A B C D

Feedback Methyl methacrylate is a common monomer used to make complete dentures. Methyl methacrylate is a common monomer used to make complete dentures. Monomers are small compounds, while polymers chemically link into long chains. Polymerization chemically links small organic compounds called monomers into long chains of repeating monomer (“mer”) subunits. A single polymer chain commonly contains 10,000 to 100,000 linked monomer subunits.

DIF: Comprehension REF: p. 169 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. Which of the following is not a by-product produced during polymerization? a. Water b. Alcohol c. Free radicals d. Hydrogen gas ANS: B

A B C D

Feedback Water is a by-product of polymerization. Alcohol is a by-product of polymerization. Free radicals are not by-products of polymerization. Hydrogen gas is a by-product of polymerization.

DIF: Knowledge REF: p. 171 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. Not all monomers may be able to participate in the polymerization reaction. Any unreacted

residual monomer in the polymer will not have significant clinical consequences. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B C D

DIF: Comprehension REF: p. 171 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 29. Which method of polymerization uses monomers that have a carbon–carbon double bond as

their reactive group? a. Poly(methyl methacrylate) b. Residual monomer c. Free radical d. Addition ANS: C

A B C D

Feedback Poly(methyl methacrylate) is a common acrylic used to construct dentures. Residual monomer is unreacted monomer in the polymer. Free-radical polymerization uses monomers that have a carbon–carbon double bond as their reactive group. No by-product is formed.

DIF: Knowledge REF: p. 171 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver,

and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 30. Which of the following statements is correct regarding addition polymerization? a. It has a high exothermic reaction. b. It has a low exothermic reaction. c. It does not create by-products. d. All of the above are correct. e. Only A and C are correct. ANS: E

A B C D E

Feedback A and C are both correct. It has a high exothermic reaction. A and C are both correct. Only A and C are correct. Addition polymerization is preferred in dentistry, because without reaction by-products, there is no risk of leaching of the by-product, which can increase shrinkage of the polymer or toxic reactions to the patient. It is highly exothermic.

DIF: Comprehension REF: p. 172 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

TESTBANKSELLER.COM

31. Which of the following is correct regarding cross-linked acrylic polymers? a. More rigid b. Less soluble c. Less temperature resistant d. Only A and B e. Only B and C ANS: D

A B C D E

Feedback Only A and B are correct. Only A and B are correct. Only A and B are correct. Cross-linked acrylic polymers are more rigid and less soluble than their non-cross-linked counterparts. Only A and B are correct.

DIF: Comprehension REF: p. 172 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. What is a homopolymer? a. Contains multiple types of monomers

b. Contains one type of monomer c. Contains no monomer d. Does not polymerize ANS: B

A B C D

Feedback The polymer strands contain only one type of monomer. The acrylics discussed so far are homopolymers; that is, the polymer strands contain only one type of monomer. The polymer strands contain only one type of monomer. A homopolymer uses a free-radical polymerization process.

mouth protectors, and restorative composites. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

DIF: Knowledge REF: p. 172 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. Which of the following statements is correct about plasticizers? a. Liquid oils such as dibutyl phthalate will cause a PMMA to become rigid. b. The chemicals in plasticizers do not participate in the polymerization process. c. The chemicals do not become part of the polymer strands but are trapped in the

network. d. Only A and B are correct. e. Only B and C are correct. ANS: E

A B

Feedback Liquid oils such as dibutyl phthalate will cause a PMMA to become rubbery. B and C are both correct.

C D E

B and C are both correct. Only B and C are correct. On occasion, chemicals called plasticizers are added to a polymer that do not participate in the polymerization reaction and do not become part of the polymer strands yet are trapped in the polymer network.

DIF: Comprehension REF: p. 173 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 35. Why are filler particles often bonded to the polymer network? a. Increase strength b. Reduce water sorption c. Stabilize the color or transparency d. Only A and B are correct. e. Only A and C are correct. ANS: D

A B C D

Feedback Only A and B are correct. Only A and B are correct. Only A and B are correct. Fillers are particles that are often bonded to the polymer network to increase strength, reduce water sorption, or change the color or transparency of the polymer. Filler particles are often bonded to the polymer network to change the color or transparency of the polymer.

DIF: Comprehension REF: p. 173 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. The denture base material should be a. doughlike b. grainy-sandy c. sticky-stringy d. viscous-flowing

before packing into the flask.

ANS: A

A B C D

Feedback Within a few minutes, the mixture becomes doughlike, and it is in this stage that the material is packed into the denture flask. Initially the mixture is grainy or sandy. It then rapidly becomes sticky and stringy. Viscosity and flow are not measured conditions.

in the monomer liquid that

mixes with the benzoyl peroxide in the polymer powder. a. fillers b. plasticizers c. accelerators d. free radicals ANS: C

A B C D

Feedback Fillers increase strength. Plasticizers make the resin more flexible. When the accelerator is combined with the benzoyl peroxide in the powder, free radicals are produced, and polymerization begins. Free radicals are produced.

DIF: Knowledge REF: p. 177 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. Soft liners are used for patients with minimal undercuts of the edentulous ridges. They are

EhSoTseBrAidNgK also used for those patientsTw esSaE reLcLoE ntR in. uaClO lyMsore. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Soft liners are used for patients with severe undercuts of the edentulous ridges or for those patients whose ridges are continually sore. Soft liners are used for patients with severe undercuts of the edentulous ridges or for those patients whose ridges are continually sore. Soft liners are used for patients with severe undercuts of the edentulous ridges or for those patients whose ridges are continually sore. Soft liners are used for patients with severe undercuts of the edentulous ridges or for those patients whose ridges are continually sore.

DIF: Analysis REF: p. 182 OBJ: 9 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39. Which of the following is correct about maxillofacial prostheses?

a. b. c. d.

They are inflexible and difficult to retain. The edges are thick and esthetics are poor. Difficult to match a person’s skin tone and coloring. Materials with better properties have not been developed since the late 1980s.

ANS: D

A B C D

Feedback The prostheses are flexible and will remain soft through a high range of temperature changes. The edges are very thin so that they blend in but are also susceptible to tearing. Pigments are added to easily match the wearer’s skin tone. These materials are used infrequently so there has been little incentive to develop better materials since the late 1980s.

DIF: Knowledge REF: p. 187 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. How long does it take for a chemically cured custom impression tray to polymerize? a. 2 to 4 minutes b. 4 to 7 minutes c. 6 to 10 minutes d. 8 to 10 minutes ANS: C

A B C D

Feedback Polymerization of a custom impression tray will take 6 to 10 minutes before being disturbed or removed from the model. 2 to 4 minutes is insufficient time. Polymerization of a custom impression tray will take 6 to 10 minutes before being disturbed or removed from the model. 4 to 7 minutes is insufficient time. Polymerization of a custom impression tray will take 6 to 10 minutes before being disturbed or removed from the model. Polymerization of a custom impression tray will take 6 to 10 minutes before being disturbed or removed from the model. 8 to 10 minutes is within the acceptable time frame.

DIF: Analysis REF: p. 189 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to 1. custom-cured impression trays. MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Resin composite temporary materials are chemical cured. Resin composite temporary crowns

wear better than their acrylic counterparts. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect.

ANS: C

Feedback Resin composite temporary materials come in light-cured, chemical-cured, and dual-cured applications. Resin composite temporary materials also wear better than acrylic temporary materials. Resin composite temporary materials come in light-cured, chemical-cured, and dual-cured applications. Resin composite temporary materials also wear better than acrylic temporary materials. Resin composite temporary materials come in light-cured, chemical-cured, and dual-cured applications. Resin composite temporary materials also wear better than acrylic temporary materials. Resin composite temporary materials come in light-cured, chemical-cured, and dual-cured applications. Resin composite temporary materials also wear better than acrylic temporary materials.

DIF: Comprehension REF: p. 188 OBJ: 12 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Apply the steps to acceptable denture care. ANS:

• • • • •

Store wet when not in the mouth Use a soft bristle brush to clean away debris and plaque Use a cleaning paste made specifically for dentures. Oral dentifrices are too abrasive and will scratch the acrylic. Avoid excessive brushing as it may wear down the acrylic and compromise the fit of the denture. Overnight immersion in 5% hypochlorite and Calgon™ will disinfect the denture acrylic.

DIF: Application REF: p. 182 OBJ: 8 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Compare and contrast methyl methacrylate polymers with cross-linked polymers. ANS:

Poly(methyl methacrylate), or PMMA, is the most common acrylic polymer used in prosthodontics. It is formed by an addition polymerization from methyl methacrylate, initiated by free radicals. PMMA is used for complete and partial dentures, temporary crowns, and several other prosthodontic restorations. Cross-linking during polymerization changes the properties of polymers by chemically linking polymer chains together. Linked chains are more rigid, providing more stability for the prosthesis during use, and are resistant to dietary “solvents” such as wine.

These types of acrylics are homopolymers, meaning there is only one monomer used in the process. DIF: Analysis REF: p. 180 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures A, Describe how to prepare, mix, deliver, and store restorative materials, including but not limited to 1. acrylic products or acrylic substitutes MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

Chapter 14: Dental Ceramics Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. What is porcelain composed of? a. Feldspar b. Quartz c. Silica d. A and B are correct. e. B and C are correct. ANS: D

A B C D E

Feedback A and B are correct. A and B are correct. A and B are correct. Silica is not a component of porcelain. Porcelain refers to ceramics composed mainly of feldspar, quartz, and kaolin. A and B are correct.

DIF: Comprehension REF: p. 192 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Which properties listed is(are) correct regarding ceramics? a. Are opaque b. Are translucent c. Have low corrosion and wear d. A and C e. B and C ANS: E

A B C D E

Feedback Ceramics are translucent unless opaquers are added. B and C are both correct. B and C are both correct. B and C are correct. Ceramics are translucent and have low corrosion and wear.

DIF: Knowledge REF: p. 202 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 3. What is the most common application of ceramics in dentistry today? a. Denture teeth

b. Porcelain-jacket restorations c. Ceramic–alloy restorations d. All-ceramic restorations ANS: C

A B C D

Feedback Ceramic denture teeth are rarely used today. Porcelain-jacket crowns have low strength. Ceramic–alloy restorations are the most common application of ceramics in dentistry today. All-ceramic restorations are rapidly becoming the treatment of choice.

DIF: Knowledge REF: p. 192 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. What is(are) the primary ingredient(s) of dental porcelain? a. Silica b. Quartz c. Feldspar d. A and B are correct. e. A and C are correct. ANS: E

A B C D E

Feedback A and C are correct. A and C are correct. Quartz is not a component of porcelain. A and C are correct. Dental porcelain is manufactured primarily from feldspar, silica, and alumina. A and C are correct.

DIF: Knowledge REF: p. 193 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. Which of the following statement(s) is(are) true of fluxes formed during the fabrication of

dental ceramics? a. Fluxes cause the ceramic to be more opaque. b. Fluxes require a higher fusing temperature. c. Fluxes disrupt the crystal lattice. d. A, B, and C are true statements. e. A and C are true statements. ANS: C

Feedback Fluxes cause the ceramic to be more translucent.

B C D E

Fluxes have a lower fusing temperature. Fluxes disrupt the crystalline array. Only C is correct. Only C is correct.

DIF: Comprehension REF: p. 192 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. What is leucite? a. Crystalline phase that forms under certain conditions within the glassy phase of

dental ceramics b. Oxide layer that forms on the surface of the alloy substructure c. By-product that forms on the surface of dental porcelain d. Amorphous non-crystalline phase in dental ceramics ANS: A

A B C D

Feedback Leucite is a crystalline phase that forms under certain conditions within the glassy phase of dental ceramics. Flux removes oxidation. Leucite is an additive. Leucite is part of the crystalline phase.

DIF: Knowledge REF: TpE . S1T 93BANKS OE BJ:LLE 1 R.COM TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. The fusing temperature of a medium-fusing dental ceramic is a. 871; 1066 b. 1093; 1260 c. 1288; 1371 d. 1400; 1731

° C to _

° C.

ANS: B

A B C D

Feedback This is an inadequate temperature range. The fusing temperature of a medium-fusing dental ceramic is 1093° C to 1260° C. This is an excessive temperature range. This is an excessive temperature range.

8. When would a high-fusing type of dental ceramics be used? a. Fabricate some all-ceramic restorations b. Make some all-ceramic restorations c. Fabricate porcelain-jacket crowns d. Make ceramic–alloy restorations e. Make denture teeth ANS: E

A B C D E

Feedback Indirect ceramic restorations are made using medium-fusing dental ceramics. Indirect ceramic restorations are made using medium-fusing dental ceramics. Indirect ceramic restorations are made using medium-fusing dental ceramics. Indirect ceramic restorations are made using medium-fusing dental ceramics. High-fusing types of dental ceramics are used to make denture teeth.

DIF: Knowledge REF: p. 201 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. Which of the following statements is true regarding the color of ceramics? a. Hue is the intensity of the color. b. A low chroma indicates grayness. c. Value is the basic shade of the color. d. Chroma is the amount of lightness or darkness. ANS: B

A B C D

Feedback Chroma is the intensity of the color. A low chroma indicates grayness. Hue is the basic shade of the color. Value is the amount of lightness or darkness.

DIF: Knowledge REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. The light source is critical for proper color matching because it has a major influence on how

color appears to an observer. What is this principle? a. Reflectance b. Translucence c. Metamerism d. Transmittance ANS: C

Feedback Reflectance is the amount of incident light reflected from the surface.

B C D

Translucence is the penetration of light. The light source is critical for proper matching, because it has a major influence on how color appears to an observer, a principle called metamerism. Transmittance is the fraction of incident light.

DIF: Knowledge REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 11. In ceramic–alloy restorations, the alloy substructure is generally less than

mm thick in

areas that will be covered by the ceramic. a. 5 b. 2.5 c. 2 d. 0.5 e. 0.1 ANS: D

A B C D E

Feedback This would be too thick and interfere with occlusion. This would be too thick and interfere with occlusion. This would be too thick and interfere with occlusion. In ceramic–alloy restorations, the alloy substructure is generally less than 0.5 mm thick in areas that will be covered by the ceramic. This would be too thiT nE toSbT eB stA abNleK. SELLER.COM

DIF: Knowledge REF: p. 202 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. What is the common cause of failure of a ceramic–alloy bond? a. Formation of an oxide layer that is too thick b. Failure within the ceramic layer itself c. Failure within the alloy casting d. An inadequate oxide layer ANS: B

A B C D

Feedback The oxide layer is controlled by flux. The most common failure of the ceramic–alloy bond is caused by failure within the ceramic layer itself. Ceramic would not be bonded to a failed casting. The oxide layer is controlled by flux.

DIF: Knowledge REF: p. 204 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of

laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. The ceramic should have a coefficient of thermal expansion

than that of the alloy

in most cases. a. significantly greater b. significantly less c. slightly greater d. slightly less ANS: B

Feedback The coefficient of thermal expansion of the ceramic should be slightly less than that of the core material. Other extremes would be detrimental to the efficacy of the restoration. The coefficient of thermal expansion of the ceramic should be slightly less than that of the core material. Other extremes would be detrimental to the efficacy of the restoration. The coefficient of thermal expansion of the ceramic should be slightly less than that of the core material. Other extremes would be detrimental to the efficacy of the restoration. The ceramic should have a coefficient of thermal expansion slightly less than that of the alloy in most cases.

DIF: Knowledge REF: p. 204 OBJ: 4 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 14. Why is the alloy substructure degassed in a ceramic oven during fabrication of a

ceramic–alloy restoration? a. Remove organic impurities from the alloy surface. b. Promote the formation of an oxide layer on the alloy. c. Remove hydrogen cyanide gas formed during the metal casting process. d. A, B, and C are all correct. e. Only A and B are correct. ANS: E

A B C D E

Feedback A and B are both correct. A and B are both correct. There is no evolution of gas in the process. Only A and C are correct. During fabrication of a ceramic–alloy restoration, the alloy substructure is degassed in a ceramic oven to remove organic impurities from the alloy surface and promote the formation of an oxide layer.

DIF: Comprehension

REF: p. 204

OBJ: 4

TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. Which type of ceramic is applied to the ceramic–alloy restoration in order to hide the color of

the alloy? a. Gingival b. Opaque c. Incisal d. Body e. Glaze ANS: B

A B C D E

Feedback Gingival surface ceramic is placed over the opaque material. Opaque ceramic is applied to the ceramic–alloy restoration to hide the oxide of the alloy. Incisal edge ceramic is placed over the opaque material. Thickness of the body of the ceramic–alloy restoration precludes need to opaque. Glaze is added last.

DIF: Knowledge REF: p. 205 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

TESTBANKSELLER.COM

16. During firing, what is the process called when the particles of ceramic melt together at their

edges? a. Rheology b. Sintering c. Abfraction d. Condensation ANS: B

A B C D

Feedback Rheology is the study of the flow of matter. During firing, the particles of ceramic melt together at their edges in a process called sintering. Abfraction is loss of tooth structure from flexural forces. Condensation is the process in which a viscous slurry of the porcelain particles in water or water–glycerol is applied to the substructure, using vibration.

DIF: Knowledge REF: p. 196 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. What is the principal advantage of any all-ceramic crown in contrast to a ceramic–alloy

crown?

a. b. c. d.

Simpler manufacturing process Superior fracture resistance Excellent esthetics Lower cost

ANS: C

A B C D

Feedback The manufacturing process is complex. There is a higher fracture potential. The principal advantage of any all-ceramic crown may often be excellent esthetics. The cost is higher.

DIF: Knowledge REF: p. 206 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. Which of the following statements is(are) true of all-ceramic restorations that use a

high-strength core ceramic beneath traditional porcelains? a. The core ceramic is used for the entire restoration. b. The high-strength core replaces the alloy substructure. c. CAD–CAM techniques may be used to design and cut the core material out of a block of high-strength starting material. d. A and C are correct. e. B and C are correct. ANS: D

A B C D E

Feedback B and C are both correct. The core ceramic is not used for the entire restoration. B and C are both correct. B and C are both correct. The high-strength core replaces the alloy substructure, and CAD–CAM techniques may be used to design and cut the core material out of a block of high-strength starting material.

DIF: Comprehension REF: p. 206 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 19. The decision to use an all-ceramic restoration is most controversial for which restoration listed

below? a. Anterior crowns b. Anterior bridges c. Posterior crowns d. Posterior bridges

ANS: D

A B C D

Feedback Stresses on these restorations are not as great as on posterior bridges. Stresses on these restorations are not as great as on posterior bridges. Stresses on these restorations are not as great as on posterior bridges. The decision to use an all-ceramic restoration is most controversial for posterior bridges.

DIF: Knowledge REF: p. 206 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 20. Which of the following are limitations of all-ceramic restorations when contrasted with

ceramic–alloy restorations? a. They will fracture in service more often than ceramic–alloy restorations. b. The fit of many all-ceramic restorations is not as precise as their ceramic–alloy counterparts. c. All-ceramic restorations require the removal of more tooth structure than ceramic–alloy restorations. d. A, B, and C are all limitations. e. Only A and B are limitations. ANS: D

A B C D

Feedback A, B, and C are all correct. A, B, and C are all correct. A, B, and C are all correct. All-ceramic restorations will fracture in service more often than ceramic–alloy restorations; they require the removal of more tooth structure than ceramic–alloy restorations to try to limit fractures; and the fit of many all-ceramic restorations is not as precise as their ceramic–alloy counterparts. A, B, and C are all correct.

DIF: Comprehension REF: p. 206 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 21. Ceramic veneers are used most often on a. maxillary anterior b. maxillary posterior c. mandibular anterior d. mandibular posterior ANS: A

Feedback

teeth.

A B C D

Veneers are used most often on maxillary anterior teeth. Veneers are only used on anterior teeth. Veneers are used most often on maxillary anterior teeth. Veneers are only used on anterior teeth.

DIF: Knowledge REF: p. 209 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Veneers are bonded to the tooth using a. resin-based b. chemical-cured c. shade-controlled d. A, B, and C are all correct. e. Only A and C are correct.

cements and acid-etching techniques.

ANS: E

A B C D E

Feedback Only A and C are correct. Bonding materials for veneers are light activated. Only A and C are correct. Only A and C are correct. Veneers are bonded to the tooth using resin-based, shade-controlled, and light-activated cements and acid-etching techniques.

DIF: Comprehension REF: p. 209 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Ceramic inlays are generally cemented using a. zinc polycarboxylate b. zinc oxide–eugenol c. zinc phosphate d. resin-based

cements.

ANS: D

A B C D

Feedback Using a bonded cement is critical in the success of the restoration. Using a bonded cement is critical in the success of the restoration. Using a bonded cement is critical in the success of the restoration. Ceramic inlays are generally cemented using resin-based cements.

24. Which statement is true when contrasting ceramic inlays and composite to esthetically restore

small posterior lesions? a. Composites require more chair time. b. Ceramic inlays use a less aggressive tooth preparation. c. Ceramic inlays require more manipulation of materials by the practitioner. d. Composites are less customizable in terms of shade, shape, and restoration design. ANS: A

A B C D

Feedback When contrasting ceramic inlays versus composite to esthetically restore small posterior lesions, composites require more chair time. Preparation for inlay is more aggressive. Composites require much more clinical finesse. Customization of composites is easier.

DIF: Knowledge REF: p. 209 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. Which material is used intraorally to repair fractured ceramic restorations? a. Ceramic b. Hybrid ionomer c. Resin composite d. Methyl methacrylate ANS: B

A B C D

Feedback In most cases the most prudent resolution to the damage is to replace the restoration. In most cases the most prudent resolution to the damage is to replace the restoration. Resin composite may be used in the mouth to repair a broken ceramic restoration. In most cases the most prudent resolution to the damage is to replace the restoration.

DIF: Knowledge REF: p. 209 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. At the atomic level, ceramics are composed of metala. hydrogen b. glycerol c. oxygen d. silica

ionic bonds.

ANS: C

A B C D

Feedback Hydrogen is an element on the periodic table that can be used as an alternate fuel source. Glycerol is a colorless, odorless, syrupy, sweet liquid. At the atomic level, ceramics are composed of metal–oxygen ionic bonds. Silica is a dioxide of silicon occurring specifically in quartz.

DIF: Knowledge REF: p. 192 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. Which common metallic element(s) occurs in ceramics in combination with oxygen? a. Silica b. Zirconium c. Aluminum d. A and C are correct. e. B and C are correct. ANS: E

A B C D E

Feedback B and C are both correct. B and C are both correct. B and C are both corrT ecEt.STBANKSELLER.COM Silica is not a metallic element in the process. Silicon (Si), zirconium (Zr), and aluminum (Al) are common metallic elements that occur in ceramics in combination with oxygen. Silica is not a metallic element in the process.

DIF: Comprehension REF: p. 192 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. The terms ceramic and porcelain are often used interchangeably. Porcelain is a type of

ceramic that results when feldspar, silica, and alumina are fired together with fluxes. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

Feedback The terms ceramic and porcelain are often used interchangeably but incorrectly. Ceramic refers to any material composed of the arrays of metal–oxygen bonds described above. Porcelain, on the other hand, is a type of ceramic that results

B C D

when feldspar (K2O-Al2O3-SiO2), silica (SiO2), and alumina (Al2O3) are fired together with fluxes. Both statements are correct. Both statements are correct. Both statements are correct.

ceramics are the oldest of the dental ceramics and very esthetic, but they are relatively weak. a. Leucite b. Crystalline c. Feldspathic d. Amorphous ANS: C

A B C D

Feedback Leucite, small islands of a crystalline phase, results when feldspar silica and aluminum are fired together with sodium carbonate or potassium carbonate. During the firing of feldspar and aluminum, large areas of amorphous ceramic are formed, with small islands of a crystalline phase called leucite. Feldspathic ceramics are the oldest of the dental ceramics and very esthetic, but they are relatively weT akE. STBANKSELLER.COM Amorphous is a term used to describe ceramic crystalline arrays.

DIF: Knowledge REF: p. 193 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 30. What does leucite do to porcelain? a. Makes it stronger b. Makes it lower fusing c. Makes it more translucent d. Makes it lower expanding ANS: B

A B C D

Feedback Leucite makes the porcelain more opaque, stronger, higher fusing, and higher expanding upon heating. Leucite makes the porcelain higher fusing. Leucite makes the porcelain more opaque. Leucite makes the porcelain higher expanding.

DIF: Knowledge

REF: p. 193

OBJ: 3

TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 31. Which technique(s) is(are) used to form one-step dental restoration? a. Stacking b. Machining c. Condensing d. Only A and B e. Only B and C ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. The green state is achieved through a process called condensation. Only A and B are correct. Techniques that are used to form the final dental restoration include stacking, infusing, pressing, and machining.

DIF: Knowledge REF: p. 195 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 32. Which of the following are other techniques used to form ceramic restorations? TESTBANKSELLER.COM a. Casting b. Stacking c. Pickling d. Sintering ANS: C

A B

C D

Feedback Casting is not a frequently used technique for ceramic restorations. In stacking, the parent ceramic is ground into particles that are manipulated into an approximation of the final form in a “green” or weak state. The green state is achieved through a process called condensation. After forming the green state, the ceramic is fired in a process called sintering. Pickling is the immersion of new cast into a hot acid bath.

DIF: Knowledge REF: p. 196 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 33. Which is an advantage of milling a ceramic crown? a. It is a one-step process. b. Green state is maximized. c. Laboratory turnaround is minimized.

d. It requires an elastomeric impression. ANS: A

C D

Feedback Newer ceramics are machined into final form; no condensation or sintering or melting is needed. The replica of the tooth preparation is scanned into a computer, and then a highly sophisticated program drives fine machining tools to mill the ceramic block to the final form, usually in several minutes. Because there are no heat and no condensation, shrinkage associated with stacked ceramics is not an issue (although there is some shrinkage associated with ceramics milled in a green state). Milled ceramic crowns are milled in-house in the same appointment. Impressions are digital.

DIF: Knowledge REF: p. 198 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. Ceramics exhibit extremely

compressive strengths and moduli but relatively

tensile strengths and elongation. a. low; low b. low; high c. high; low d. high; high ANS: C

A B C D

Feedback Ceramics exhibit extremely high compressive strengths and moduli but relatively low tensile strengths and elongation. Ceramics exhibit extremely high compressive strengths and moduli but relatively low tensile strengths and elongation. Ceramics exhibit extremely high compressive strengths and moduli but relatively low tensile strengths and elongation. Ceramics exhibit extremely high compressive strengths and moduli but relatively low tensile strengths and elongation.

DIF: Comprehension REF: p. 199 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 35. What will a high-flexural-strength ceramic suggest? a. Better resist fracture b. Be susceptible to fracture c. Have a low clinical survival rate d. Only A and C e. Only B and C

ANS: A

A B C D E

Feedback Based on empirical evidence, a high flexural strength suggests that a ceramic will better resist fracture in clinical service. It will have better resistance to fracture. It will have a high clinical survival rate. A is the only correct answer. A is the only correct answer.

DIF: Comprehension REF: p. 199 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. Amorphous ceramic phases are stronger and less soluble than crystalline phases. A pure

amorphous phase is transparent, like window glass. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorreT ctE; S stT atB em t 2SiEs L coLrE reR ct. . COM AeNnK Amorphous ceramic phases are weaker and more soluble than crystalline phases. A pure amorphous phase is transparent, like window glass. Statement 1 is incorrect; statement 2 is correct.

DIF: Comprehension REF: p. 195 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 37. How are glassy porcelains classified? a. Fusing temperature b. Sintering temperature c. Coefficient of thermal expansion d. A, B, and C are all factors. e. Only A and B are correct. ANS: E

A B C D

Feedback A and B are both correct. A and B are both correct. The coefficient of thermal expansion is the degree of expansion and contraction. Only A and B are correct.

Glassy porcelains are classified according to their fusing temperature (also called sintering temperature).

DIF: Comprehension REF: p. 201 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. What is the amount of lightness or darkness of a ceramic restoration called? a. Hue b. Color c. Value d. Chroma ANS: C

A B C D

Feedback Hue is the basic shade of the color. Color results when a material reflects light from within, but the wavelength (or color) of the reflected light is changed. Value is the amount of lightness or darkness. Chroma is the intensity of the color.

DIF: Knowledge REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General TESSupp TBorAtiN 39. Which of the following is not true about ceramic restorations? a. Esthetically superior b. Easily fixed if broken c. Few biocompatibility issues d. Significant wear of the antagonist ANS: C

A B C D

Feedback Esthetically, ceramic restorations are superior to other types of restorations including composites. If broken, ceramic restorations are very difficult to repair. Ceramics restorations are biocompatible in most cases. Because of their hardness, ceramic restorations wear down the opposing tooth.

DIF: Knowledge REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. An all-ceramic crown is often composed of a low-strength opaque ceramic core with a bonded

veneer of a stronger but translucent glassy or glass-dominated ceramic. Newer designs have only high-strength crystalline or crystalline-dominated ceramics.

a. b. c. d.

Statement 1 is correct; statement 2 is correct. Statement 1 is correct; statement 2 is incorrect. Statement 1 is incorrect; statement 2 is correct. Statement 1 is incorrect; statement 2 is incorrect.

ANS: C

C D

Feedback An all-ceramic crown is often composed of a high-strength translucent ceramic core with a bonded veneer of a weaker but opaque glassy or glass-dominated ceramic. An all-ceramic crown is often composed of a high-strength translucent ceramic core with a bonded veneer of a weaker but opaque glassy or glass-dominated ceramic. Newer designs have only high-strength crystalline or crystalline-dominated ceramics. An all-ceramic crown is often composed of a low-strength opaque ceramic core with a bonded veneer of a stronger but translucent glassy or glass-dominated ceramic. Newer designs have only high-strength crystalline or crystalline-dominated ceramics.

DIF: Comprehension REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. What is one of the newest T apEpS licTaB tiA onNsKfoSrEdL enLtaEl R ce.raCmOiM cs? a. Implant abutments b. Multi-unit bridges c. Denture teeth d. A, B, and C are all new applications for dental ceramics. ANS: A

A B C D

Feedback Implant abutments made of ceramic instead of titanium are being used to replace the gray core of the implant. Multi-unit bridges made of ceramic have been used for years. Denture teeth made of ceramics are used infrequently today. Only A is correct.

DIF: Knowledge REF: p. 209 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Identify the three color factors assessed in teeth, and explain why each is important to

esthetics.

ANS:

Color results when a material reflects light from within but the wavelength (or color) of the reflected light is changed. The material absorbs some of the light. Hue is the basic shade of color, such as green, yellow, or blue. Chroma is the intensity of the color, such as pale blue to brilliant blue. A low chroma indicates grayness. Value is the amount of lightness or darkness. A high value (up to 10) implies lightness, whereas a low value implies darkness. A value of zero is black, regardless of the hue or chroma. Among hue, value, and chroma, value is the most critical parameter for matching the color of ceramics with teeth because the hue and chroma occur within a relatively narrow range for most natural teeth. DIF: Analysis REF: p. 202 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Compare and contrast traditional ceramic restorations with machine-milled ceramic

restorations. Give advantages and disadvantages of each. ANS:

Feldspathic ceramics (porcelains) are glassy ceramics that form from the combination of feldspar, silica, and alumina; feldspathic ceramics are the oldest of the dental ceramics and are very esthetic but relatively weak. Fabrication is a multiple step technique that requires the patient to schedule two or more appointments. These types of ceramic restorations are difficult to repair if broken. Esthetically they are superior. Ceramic restorations constructed using the milling process takes only one appointment. The tooth may be prepared, scaT nne siA ngNaKC ware, and milled within a couple of ESdTuB SA ED L/LCEARM.sCoOftM hours. Overall success rate is high, although if the patient has a ceramic core on the tooth, the restoration may debond. DIF: Analysis REF: p. 206 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (ceramics) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

Chapter 15: Dental Implants Powers: Dental Materials, 11th Edition MULTIPLE CHOICE 1. The bone is prepared for an endosseous dental implant with special metallic burs driven at a. b. c. d.

speeds high; without slow; without high; with slow; with

water cooling.

ANS: D

A B C D

Feedback The temperature needs to remain at physiological levels to avoid bone damage. Speeds should be <2000 rpm. The metallic burs need to be driven with water cooling. Speeds should be <2000 rpm. The bone is prepared for an implant with special metallic burs driven at slow speeds with water cooling.

DIF: Knowledge REF: p. 214 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 ProvidiT ngESSuT ppB orAtiN veKTSreEaL tmLeE ntRS. erC viO ceM s, 6.5 General 2. During bone removal for implant placement, the objective is to avoid temperatures in the bone

above a. 10 b. 17 c. 27 d. 37 e. 47

° C.

ANS: D

A B C D E

Feedback This temperature is within an acceptable range for the procedure. This temperature is within an acceptable range for the procedure. This temperature is within an acceptable range for the procedure. During bone removal for implant placement, the objective is to avoid temperatures in the bone above 37° C. This temperature exceeds the recommended limit.

3. What will occur if bone is heated to high temperatures during implant placement? a. Damage tissue b. Trigger inflammation c. Promote rapid healing d. A and B are correct. e. A and C are correct. ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. Inflammation inhibits healing. High temperatures in bone during implant placement will damage tissue and trigger inflammation. A and B are correct.

DIF: Comprehension REF: p. 214 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 4. Burs for preparation of the implant site are composed of which type of special alloy? a. Nickel b. Titanium c. Platinum d. Stainless steel ANS: B

A B C D

Feedback Titanium is used to prevent deposit of trace elements. Burs for preparation of the implant site are composed of special alloys of titanium. Titanium is used to prevent deposit of trace elements. Titanium is used to prevent deposit of trace elements.

DIF: Knowledge REF: p. 214 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 5. How is the endosseous implant placed once the implant site is prepared? a. Pounding it into place with a small hammer b. Screwing the implant into the site c. Friction-fitting the implant d. Both A and B e. Both B and C ANS: E

A B C D E

Feedback Pounding it into place with a small hammer would cause irreparable trauma and damage. B and C are both correct. B and C are both correct. Only B and C are correct. Once the implant site is prepared in bone, the implant is placed by screwing the implant into the site or friction-fitting the implant.

DIF: Comprehension REF: p. 215 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 6. During two-step endosseous implant placement, a

is placed on top of the implant to cover internal threads once the implant is placed into bone. a. temporary acrylic spacer b. temporary stayplate c. space maintainer d. healing cap ANS: D

A B C D

Feedback Once the endosseous implant and cap are placed, no other means of managing space is needed unlesT s tEim e.LLER.COM SeTiBs AanNiKssSuE Once the endosseous implant and cap are placed, no other means of managing space is needed unless time is an issue. Once the endosseous implant and cap are placed, no other means of managing space is needed unless time is an issue. Once the implant is in place, a healing cap is placed on top of the implant to cover internal threads.

DIF: Knowledge REF: p. 217 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 7. An endosseous implant is allowed to heal for at least

two-step placement of an implant. a. 2 days b. 2 weeks c. 6 weeks d. 6 months e. 2 years ANS: C

Feedback

during the first stage of a

A B C D E

Two days is not enough time for osseointegration to occur. Two weeks is not enough time for osseointegration to occur. An implant is allowed to heal for at least 6 weeks during the placement of an implant. Six months is an excessive time frame. Two years is an excessive time frame.

DIF: Knowledge REF: p. 217 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 8. What occurs during the second stage of a two-stage implant placement where a second

surgery is performed to remove the healing caps? a. Recontour the osseous crest of bone b. Recontour gingival tissue c. Place the abutment caps d. Place the abutments ANS: C

A B C D

Feedback This is a stage-one procedure. This is a stage-one procedure. During the second stage of a two-stage implant placement, a second surgery is performed to remove the healing caps and place the abutment caps. The abutments are plaTcE edSaTftB erAtN heKsSoE ftLtiL ssE ueRh.aCs O heMaled around the abutment caps.

DIF: Knowledge REF: p. 216 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 9. When the prosthesis is screwed into place, which part of the implant does it thread into? a. Preparation b. Healing cap c. Abutment d. Bone ANS: C

A B C D

Feedback The implant is placed into the prepared bone. At this point in treatment, healing caps are no longer present. The prosthesis is most commonly screwed into place with a small screw that penetrates the top of the crowns and threads into the abutment. The implant is placed into the prepared bone.

DIF: Knowledge

REF: p. 219

OBJ: 4

TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 10. Which of the following statements is(are) true of single-stage implant placement? a. It requires simultaneous hard and soft tissue healing around the implant. b. Occlusal loading of the implant occurs within days of placement. c. Peri-implantitis occurs if there is too much initial loading. d. A, B, and C are true statements. e. A and C are true statements. ANS: E

A B C D E

Feedback A and C are correct. No occlusal loading of the implant occurs for a period of several months. A and C are correct. Only A and C are correct. Single-stage implant placement requires simultaneous hard and soft tissue healing around the implant, and no occlusal loading of the implant occurs for a period of several months.

DIF: Knowledge REF: p. 217 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

TESTBANKSELLER.COM

11. Which of the following materials promotes osseointegration? a. Beryllium alloys b. Dental amalgam c. Titanium alloys d. Stainless steel e. Nickel alloys ANS: C

A B C D E

Feedback Beryllium alloys are unacceptable alternatives due primarily to biocompatibility. Dental amalgam is an unacceptable alternative due primarily to biocompatibility. Titanium alloy, titanium–aluminum–vanadium alloy, tantalum alloy, and several ceramic materials are the only materials known to promote osseointegration. Stainless steel is an unacceptable alternative due primarily to biocompatibility. Nickel alloys are unacceptable alternatives due primarily to biocompatibility.

DIF: Knowledge REF: p. 219 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 12. In order for an implant to be successful, how long must osseointegration be maintained? a. 6 weeks

b. c. d. e.

6 months The first year The first 3 years The lifetime of the implant

ANS: E

A B C D E

Feedback A successful implant is maintained for a lifetime. Anything less is considered failure of the implant. A successful implant is maintained for a lifetime. Anything less is considered failure of the implant. A successful implant is maintained for a lifetime. Anything less is considered failure of the implant. A successful implant is maintained for a lifetime. Anything less is considered failure of the implant. For an implant to be successful, osseointegration must be maintained for the lifetime of the implant.

DIF: Knowledge REF: p. 219 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 13. Occlusal forces on natural teeth favor bone maintenance. Occlusal loads on dental implants

are transmitted to bone mostly by compressive forces and improve osseointegration. a. Statement 1 is correct; T stE atS em 2K isScE orL reLctE. R.COM TeBnAt N b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

B C

Feedback Statement 1 is correct; statement 2 is incorrect. Occlusal loads on dental implants are transmitted to bone mostly by compressive forces and tend to resorb bone over time. Statement 1 is correct; statement 2 is incorrect. Statement 1 is correct; statement 2 is incorrect. Occlusal loads on dental implants are transmitted to bone mostly by compressive forces and tend to resorb bone over time. Statement 1 is correct; statement 2 is incorrect. Occlusal loads on dental implants are transmitted to bone mostly by compressive forces and tend to resorb bone over time.

DIF: Comprehension REF: p. 220 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

14. Which type of implant-supported prosthesis is most likely to fail? a. Single crown b. Mandibular complete denture c. Maxillary complete denture d. Multiple tooth endosseous implant not connected to natural teeth e. Multiple tooth endosseous implant connected to natural teeth ANS: E

A B C D E

Feedback This is a clinical application with high success rates. This is a clinical application with high success rates. This is a clinical application with high success rates. This is a clinical application with high success rates. A multiple-tooth endosseous implant connected to natural teeth is still not common because these prostheses commonly fail.

DIF: Knowledge REF: p. 220 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 15. For most clinical situations, implant success rates are more than

% as long as the implant

osseointegrates initially and the clinical environment is not extreme. a. 50 b. 75 c. 90 d. 95 ANS: D

A B C D

Feedback Success rates go down depending on bone density and oral environment. Success rates go down depending on bone density and oral environment. Success rates go down depending on bone density and oral environment. For most clinical situations, implant success rates are more than 95%, as long as the implant osseointegrates initially and the clinical environment is not extreme.

DIF: Knowledge REF: p. 221 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 16. Which factor increases the success rate for implants? a. The density of bone is increased. b. Implants are placed with a one-step method. c. The height of bone around the implant is reduced. d. Implants are loaded immediately after placement. ANS: B

A B C D

Feedback Success rates for implants increase if the density of bone is increased. The two-step method affords a higher success rate. Bone height must be adequate to maintain the implant. Loading should not occur before osseointegration is established.

DIF: Knowledge REF: p. 221 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 17. A rate of horizontal bone loss greater than a. 0.01 b. 0.1 c. 0.3 d. 0.5

mm per year is a sign of a failing implant.

ANS: D

A B C D

Feedback This is an acceptable level of horizontal bone loss. This is an acceptable level of horizontal bone loss. This is an acceptable level of horizontal bone loss. A rate of horizontal bone loss greater than 0.5 mm/year is a sign of a failing implant.

TESTBANKSRE L:LE DIF: Comprehension EF p.R. 22C1OM OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 18. Instrumentation with

is considered to be appropriate for maintaining oral

hygiene around dental implants. a. sonic scalers b. metal scalers c. metal curettes d. plastic scalers e. ultrasonic scalers ANS: D

A B C D E

Feedback Ultrasonic and sonic scalers are contraindicated. Metal scalers are not appropriate to use on dental implants. Metal curettes are not appropriate to use on dental implants. Instrumentation with plastic scalers is considered to be appropriate for maintaining oral hygiene around dental implants. Ultrasonic and sonic scalers are contraindicated.

DIF: Knowledge

REF: p. 223

OBJ: 5

wt % is used in grade 1 commercially pure titanium

implant alloys. a. 0.01 b. 0.08 c. 0.18 d. 0.4 ANS: C

A B C D

Feedback Commercially pure titanium is inaccurate. Small amounts of other materials, 18% oxygen and trace elements, are present. Commercially pure titanium is inaccurate. Small amounts of other materials, 18% oxygen and trace elements, are present. An oxygen concentration of 18% is used in grade 1 commercially pure titanium implant alloys. Grade 4 alloys have up to 40%.

DIF: Knowledge REF: p. 224 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General

TESTBANKSELLER_.C ofOcM ommercially pure titanium alloys

20. Increasing amounts of oxygen increase the

used for endosseous implants. a. density b. strength c. ductility d. melting range e. modulus of elasticity ANS: B

A B C D E

Feedback Density is the melting point. Increasing amounts of oxygen increase the strength of commercially pure titanium alloys used for endosseous implants. Ductility is the ability of a material to be plastically deformed by elongation. Melting range is temperature range in which complete melting occurs. Modulus of elasticity is the ability of a material to elastically deform.

a. b. c. d. e.

Contains 6 wt % aluminum Contains 4 wt % vanadium Contains 4 wt % aluminum Both A and B Both B and C

ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. Aluminum and vanadium help increase tensile strength. Titanium alloy differs from commercially pure titanium, because titanium alloy contains 6% aluminum and 4% vanadium. A and B are correct.

DIF: Comprehension REF: p. 224 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 22. Which of the following statements is(are) true about the surface of commercially pure

titanium or titanium alloy? a. Both are covered with a complex mixture of adherent titanium oxides. b. Oxides rich in oxygen are closer to the surface. c. Oxides rich in oxygen are closer to the alloy. d. A and B are true statemTeE ntSs.TBANKSELLER.COM e. A and C are true statements. ANS: D

A B C D E

Feedback A and B are both correct. A and B are both correct. A and B are both correct. Both are covered with a complex mixture of adherent titanium oxides. Oxides rich in oxygen are closer to the surface. A and B are both correct.

DIF: Comprehension REF: p. 224 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 23. Scratches or other disruption of the original manufacturer's oxide layer on the surface of

endosseous implants are discouraged. Any contamination of the original surface will increase the risk of failure of the implant to osseointegrate. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct.

d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Both statements are correct. Both statements are correct. Both statements are correct. Both statements are correct.

surfaces and those with surface areas promote the greatest amounts of bone–implant contact during osseointegration of endosseous implants. a. rougher; greater b. rougher; smaller c. smoother; greater d. smoother; smaller ANS: A

A B C D

Feedback In general, rougher surfaces and those with greater surface areas promote the greatest amounts of bone–implant contact. LiLthEgRre.aCteOr M In general, rougher suTrfEacSeT sB anAdNthKoSseEw surface areas promote the greatest amounts of bone–implant contact. In general, rougher surfaces and those with greater surface areas promote the greatest amounts of bone–implant contact. In general, rougher surfaces and those with greater surface areas promote the greatest amounts of bone–implant contact.

DIF: Comprehension REF: p. 225 OBJ: 6 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 25. The thickness of most ceramic coatings on implants ranges from a. 2; 5 b. 5; 10 c. 10; 50 d. 50; 100 e. 100; 500 ANS: D

A B

Feedback This layer would be too thin to be of use. This layer would be too thin to be of use.

microns.

C D E

This layer would be too thin to be of use. The thickness of most ceramic coatings on implants ranges from 50 to 100 microns. This layer is too thick and could compromise stability.

DIF: Comprehension REF: p. 225 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 26. How long should an extraction site heal prior to placing an implant? a. 6 weeks b. 6 months c. 8 weeks d. 8 months ANS: B

A B C D

Feedback 6 weeks is insufficient healing time. Ideally, the socket area of an extracted tooth should be allowed to heal between 3 and 6 months before placing an implant. 8 weeks is insufficient healing time. Longer than 6 months is acceptable but not necessary.

DIF: Knowledge REF: p. 214 OBJ: 1 TOP: CDA, GC, IV LaboraT toE rySMTaB teA riaNlsKaS ndEP ocE edRu. reC sO B,MDemonstrate an understanding of LrL laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 27. What could occur if the temperature during the osteotomy exceeds 37° C? a. Tissue damage b. Inflammation c. Post-operative infection d. All of the above e. Only A and B are correct. ANS: D

A B C D E

Feedback A and B are correct. A and B are correct. A higher than recommended temperature would not promote infection. A higher than recommended temperature would not promote infection. If the temperature during the osteotomy exceeds 37° C, tissue damage, protein coagulation, and inflammation could occur.

MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 28. Prior to preparing the surgical site, how does the dentist determine where to place the

implant? a. Template b. Mm ruler c. Radiograph d. Custom stent e. C and D are correct. ANS: E

A B C D E

Feedback A template would not allow for differences in each individual area. A mm ruler would not be used exclusively. Dentists use radiographs or tomography to construct a custom stent. Custom stents are used to mark the surgical site of a preparation for an implant. C and D are both correct.

DIF: Comprehension REF: p. 214 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 29. Of the following types of implants, which one is seldom used today? a. Endosseous b. Transosteal c. Subperiosteal d. Both B and C ANS: C

A B C D

Feedback The endosseous implant is the most commonly used today. This implant screws directly into the bone and is retained through osseointegration. The transosteal implant is seldom used today because of the excessive and traumatic surgical procedure involved. The subperiosteal implant is seldom used today because of the excessive and traumatic surgical procedure involved. Both B and C are correct.

DIF: Comprehension REF: p. 220 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 30. Osseointegration occurs when the bone grows to within a. 1 angstrom b. 10–10 meters c. 100 angstroms d. All of the above

of the implant interface.

e. Only B and C ANS: C

A B C D E

Feedback This special interfacial condition is called osseointegration and occurs when the bone grows to within 100 Å (1 angstrom = 10–10 meters) of the titanium surface. This special interfacial condition is called osseointegration and occurs when the bone grows to within 100 Å (1 angstrom = 10–10 meters) of the titanium surface. This special interfacial condition is called osseointegration and occurs when the bone grows to within 100 Å (1 angstrom = 10–10 meters) of the titanium surface. C is the only correct answer. C is the only correct answer.

DIF: Comprehension REF: p. 219 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 31. By which method are ceramic implants retained? a. Ankylosis b. Biointegration c. Osseointegration d. All of the above e. Only A and C ANS: B

A B

C D E

Feedback Ankylosis is associated with osseointegration. For ceramic implant materials made of zirconia, the integration of the ceramic with the bone has no intervening space. Rather, a continuity exists from the implant to the bone. This interface condition is called biointegration. Osseointegration is associated with titanium implants. B is the only correct answer. B is the only correct answer.

to restore lost centric occlusion. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: B

A B C D

Feedback Endosseous implants provide an esthetic substitute for a lost or missing tooth. They also are placed to restore lost masticatory function. Endosseous implants provide an esthetic substitute for a lost or missing tooth. They also are placed to restore lost masticatory function. Endosseous implants provide an esthetic substitute for a lost or missing tooth. They also are placed to restore lost masticatory function. Endosseous implants provide an esthetic substitute for a lost or missing tooth. They also are placed to restore lost masticatory function.

DIF: Comprehension REF: p. 220 OBJ: 3 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 33. In what way were early implant strategies painful? a. Had low incidence of postoperative infection b. Required aggressive techniques c. Used biocompatible materials d. Were successful long term ANS: B

A B

C D

Feedback Early attempts to place endosseous implants failed because the surgical techniques and materials did not promote osseointegration or biointegration. These early strategiesTwEeS reTpBaA inN fuK l,SreEqL uiLreEdRa. ggCrO esM sive surgical interventions, carried high risks of postoperative infection, and were not functionally successful long term. Early attempts to place endosseous implants failed because the surgical techniques and materials did not promote osseointegration or biointegration. Early attempts to place endosseous implants failed because the surgical techniques and materials did not promote osseointegration or biointegration.

DIF: Knowledge REF: p. 220 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 34. Which of the following statements is correct regarding implant success? a. There is minimal measurable clinical mobility of the implant under occlusal

function. b. Success rates are 75% at 10 years as long as an implant osseointegrates initially. c. Some ongoing horizontal loss of bone (less than 0.8 mm per year) is common. d. Success rates decrease if the density or quantity of bone is less. ANS: D

Feedback There should be no measurable mobility.

B C D

Success rates are greater than 95% at 10 years. Horizontal bone loss should be less than 0.5 mm per year. Success rates decrease if the density or quantity of bone is less or if the implants are loaded immediately.

DIF: Knowledge REF: p. 221 OBJ: 4 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 35.

What causes peri-implantitis? a. Ineffective plaque removal b. Poor osseointegration c. High occlusal forces d. Horizontal bone loss ANS: A

B C D

Feedback Most clinicians agree that although the original periodontal anatomy is absent around an implant, a plaque-mediated inflammatory process similar to periodontal inflammation occurs. Osseointegration is essential to implant longevity. High occlusal forces can cause implant failure. Horizontal bone loss occurs naturally but should not exceed 0.5 mm per year.

DIF: Knowledge REF: TpE . S2T 21BANKS OE BJ:LLE 5 R.COM TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 36. Special instruments are needed to effectively clean titanium dental implants. What are these

instruments made of? a. Ceramic b. Teflon® c. Plastic d. Only A and C e. Only B and C ANS: E

A B C D E

Feedback Ceramic instruments would be too abrasive. B and C are both correct. B and C are both correct. Only B and C are correct. Plastic or Teflon® scalers are commonly used to clean the implant surface.

DIF: Comprehension REF: p. 221 OBJ: 5 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of

laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 37. Ceramic coatings improve bone–implant bond strengths. Their long-term stability in service is

uncertain. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: A

A B C D

Feedback Ceramic coatings improve bone–implant bond strengths, but their long-term stability in service is uncertain. Both statements are correct. Both statements are correct. Both statements are correct.

DIF: Comprehension REF: p. 225 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 38. What are the most common ceramic implants made of? a. Silica b. Quartz c. Zirconia d. Feldspar ANS: C

A B C D

Feedback Silica is used in the construction of ceramic crowns. Quartz is used in the construction of ceramic crowns. The most common ceramic implants are made of zirconia. Feldspar is used in the construction of ceramic crowns.

DIF: Knowledge REF: p. 225 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 39. In osseointegration, a layer of fibrous tissue remains to help cushion the implant.

Osseointegration involves ankyloses of the implant. a. Statement 1 is correct; statement 2 is correct. b. Statement 1 is correct; statement 2 is incorrect. c. Statement 1 is incorrect; statement 2 is correct. d. Statement 1 is incorrect; statement 2 is incorrect. ANS: C

A B C D

Feedback Osseointegration does not include a fibrous layer of tissue. The implant remains stable after osseointegration because some ankylosis occurs. Statement 1 is incorrect, and statement 2 is correct. Statement 1 is incorrect, and statement 2 is correct. Statement 1 is incorrect, and statement 2 is correct.

DIF: Comprehension REF: p. 219 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 40. Which of the following is not a true statement regarding ceramic-coated implants? a. They are held in place by biointegration. b. Their longevity has yet to be determined. c. They are preferred by clinicians over titanium implants. d. There are occasions when the ceramic coating has debonded. ANS: C

A B C D

Feedback Ceramic-coated implants are held in place through biointegration rather than osseointegration. Since these types of implants have not been on the market very long, it is unclear what their longevity will be. Titanium implants areTsEtiS ll T coBnAsiN deKrS edEtL heLsEtaRn. daCrO dM of care. There have been occasions where the ceramic coating has debonded from the surface of the implant.

DIF: Knowledge REF: p. 225 OBJ: 7 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 41. Which of the following is not a trace element found in commercially pure titanium? a. Iron b. Carbon c. Oxygen d. Hydrogen ANS: C

A B C D

Feedback Iron is a trace element found in commercially pure titanium. Carbon is a trace element found in commercially pure titanium. Oxygen is found in minimal levels instead of trace levels. Hydrogen is a trace element found in commercially pure titanium.

DIF: Knowledge

REF: p. 224

OBJ: 6

TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General SHORT ANSWER 1. Compare and contrast biointegration with osseointegration. ANS:

For dental implants made of titanium alloy, the interface between the alloy and bone must be nearly direct with no intervening fibrous tissue and as little space as possible. This special interfacial condition is called osseointegration and occurs when the bone grows to within 100 Å (1 angstrom = 10–10 meters) of the titanium surface. This degree of proximity is an extremely rigorous requirement achieved only if the surgical technique is atraumatic (see the previous discussion on surgical techniques) and the material does not have adverse biologic effects. To date, only a few materials, including commercially pure titanium, titanium– aluminum–vanadium alloy, tantalum, and several ceramic materials such as zirconia,are known to permit osseointegration. For ceramic implant materials (primarily made of zirconia at present), the integration of the ceramic with the bone has no intervening space. Rather, a continuity exists from the implant to the bone. This interfacial condition is called biointegration. Biointegration is thought to require a chemical degradation of the ceramic implant that favors bone formation and is able to integrate with the surrounding bone, which itself has a significant ceramic component. The nature of the biointegrative interface and material characteristics that promote and maintain it are not fully understood. Furthermore, the advantages of biointegration over osseointegration are not known, particularly over the long term. Both interfaces are similar to the clinical ankylosis of naT tuEraSl T teB etA hN . KSELLER.COM DIF: Analysis REF: p. 219 OBJ: 2 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General 2. Identify the major types of implants that are or have been used over the years. Compare and

contrast them and discuss why some are rarely used today. ANS:

The major types of implants used over the years include the following: transoseous, subperiosteal and endosseous. Early in modern-day implantology, most dental implants were not endosseous but were either placed between the gingiva and bone (subperiosteal implants) or designed to sandwich the mandible (transosseous implants). These early strategies were painful, required aggressive surgical interventions, carried high risks of postoperative infection, and were not functionally successful in the long term. Today, the screw type of endosseous implant has virtually supplanted all other types of implants; subperiosteal and transosseous strategies are nearly unknown. DIF: Analysis REF: p. 221 OBJ: 1 TOP: CDA, GC, IV Laboratory Materials and Procedures B, Demonstrate an understanding of laboratory procedures, including but not limited to: Unlisted topic (implants) MSC: NMDHE, 6.0 Providing Supportive Treatment Services, 6.5 General