Chapter 10: Orofacial Pain and Diseases Affecting the Temporomandibular Joint Ibsen: Oral Pathology for the Dental Hygienist, 7th Edition

Multiple Choice

1. The temporomandibular joint (TMJ) is the articulation between the condyle of the mandible and the a. zygomatic process of the temporal bone. b. glenoid fossa of the temporal bone. c. external acoustic meatus. d. spine of the sphenoid bone.

ANS: B

The TMJ is the articulation between the condyle of the mandible and the glenoid fossa of the temporal bone. It is a highly specialized joint that differs from other joints because of the fibrocartilage that covers the bony articulating surfaces, its ginglymoarthrodial movement, its function and overall health being dictated by jaw movement, and its dependence on the contralateral joint. The TMJ is the articulation between the condyle of the mandible and the glenoid fossa of the temporal bone rather than the zygomatic process of the temporal bone. The TMJ is the articulation between the condyle of the mandible and the glenoid fossa of the temporal bone rather than the external acoustic meatus. The TMJ is the articulation between the condyle of the mandible and the glenoid fossa of the temporal bone rather than the spine of the sphenoid bone.

REF: Anatomy of the Temporomandibular Joint, page 306 OBJ: 1 a. It is attached to the anterior and posterior aspects of the condyle. b. It is attached to the inferior belly of the medial pterygoid muscle. c. The disc is highly vascular. d. The disc is surrounded and protected by the fibrous connective tissue joint capsule.

2. Which statement about the articular disc in the TMJ joint is true?

ANS: D

The disc is surrounded and protected by the fibrous connective tissue joint capsule. The articular disc in the TMJ is attached to the lateral and medial rather than the anterior and posterior aspects of the condyle, to the superior belly of the lateral pterygoid muscle, and to the joint capsule. The articular disc in the TMJ is attached to the lateral and medial aspects of the condyle, to the superior rather than the inferior belly of the lateral pterygoid muscle, and to the joint capsule. The disc and the bony surfaces are avascular.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 1

3. During opening of the jaw a. rotational movement precedes translation. b. rotational movement follows translation. c. only rotational movement occurs; translation occurs only during closure. d. only translational movement occurs; rotation occurs only during closure.

ANS: A

During opening of the jaw, rotational movement precedes translation. During translation the disc assumes a more posterior position in relation to the condyle. The inferior and superior joint spaces assume different configurations during each of these movements. During opening of the jaw, rotational movement precedes rather than follows translation.

REF: Normal Function of the Temporomandibular Joint, page 308

OBJ: 1 a. Clenching, bruxism b. Whiplash injury c. Psychosocial factors d. Osteoarthritis

4. Which choice represents an indirect form of trauma affecting the TMJ?

ANS: B

Whiplash injury represents an indirect form of trauma affecting the TMJ. Trauma affecting the TMJ is classified as direct (assault), indirect (whiplash injury), or secondary to parafunctional habits (clenching, bruxism). Other contributing factors include dentofacial deformities and psychosocial factors. TMJ abnormalities are also associated with a number of different systemic diseases. Rheumatoid arthritis and osteoarthritis are the most common. Whiplash injury represents an indirect form of trauma affecting the TMJ. Trauma affecting the TMJ is classified as secondary to parafunctional habits when it is caused by clenching or bruxism.

REF: Pathophysiology of Temporomandibular Disorders, page 309

OBJ: 4

5. Clicking and popping most commonly reflect a. parafunctional habits such as bruxism and clenching. b. disc displacement with reduction. c. malocclusion. d. trismus.

ANS: B

Clicking and popping commonly reflect disc displacement with reduction. It occurs in approximately 33% of asymptomatic patients. It is of little clinical consequence in the absence of pain or other symptoms relating to the TMJ because it is controversial as to whether these noises represent an adaptive response or an early symptom of progression to disc displacement without reduction. Clicking and popping, not parafunctional habits, commonly reflect disc displacement with reduction. Clicking and popping, not malocclusion, commonly reflect disc displacement with reduction. Clicking and popping, not trismus, commonly reflect disc displacement with reduction.

REF: History, page 309 OBJ: 5 a. Panoramic imaging b. Transcranial imaging c. Computerized tomography (CT) d. Magnetic resonance imaging (MRI)

6. Which dental radiographic procedure is best for examining disc position, function, form, and the presence of joint effusions?

ANS: D

MRI is mandatory for examining disc position, function, and form and the presence of joint effusions. Arthrography may be useful when MRI is not tolerated and information regarding the position and morphology of the disc is required. Panoramic imaging radiographs are limited to identifying gross changes in bone. Transcranial imaging radiographs are limited to identifying gross changes in bone. CT is the most accurate for identifying bone abnormalities.

REF: Imaging, page 311 OBJ: 6

7. An open lock of the TMJ that the patient cannot reduce is termed a. subluxation. b. dislocation. c. ankylosis. d. myofascial pain.

ANS: B

An open lock that the patient cannot reduce is called dislocation. Dislocation occurs when one or both of the condyles translate anterior to the articular eminence. Subluxation refers to hypermobility in which the patient is able to relocate the mandible back into the glenoid fossa. Ankylosis of the TMJ is defined as immobility of the condyle because of fibrous or bony union between the articulating structures of the joint. Myofascial pain is characterized as a dysfunctional muscle hyperactivity with regional pain, tenderness of the affected muscles, and variable amounts of reduced opening and complaints of malocclusion.

REF: Hypermobility Disorders, page 312 OBJ: 7 a. It is characterized by pain that is worse in the morning. b. It is characterized by pain that is worse in the evening. c. It is an inflammatory, autoimmune disorder of the joints. d. Approximately 50% to 75% of patients have involvement of the TMJ during the course of the disease.

8. Which statement is characteristic of a patient with osteoarthritis?

ANS: B

Osteoarthritis is characterized by pain that is worse in the evening, as well as limited opening, muscle splinting, and crepitus of the TMJ. Osteoarthritis is the most common disease affecting the TMJ. In rheumatoid arthritis patients may complain of pain that is worse in the morning, limited opening, occlusal changes, and preauricular edema and tenderness. Rheumatoid arthritis is an inflammatory, autoimmune disorder of the joints. Approximately 50% to 75% of patients with rheumatoid arthritis have involvement of the TMJ during the course of the disease. Osteoarthritis is characterized by pain that is worse in the evening rather than in the morning. Rheumatoid arthritis rather than osteoarthritis is an inflammatory, autoimmune disorder of the joints. Approximately 50% to 75% of patients with rheumatoid arthritis rather than osteoarthritis have involvement of the TMJ during the course of the disease.

REF: Arthritis, page 312 OBJ: 7

9. The purpose of the synovial fluid is to a. provide nourishment and lubrication. b. divide the space into upper and lower compartments. c. govern mandibular movement. d. separate forces resulting from movement.

ANS: A

The purpose of the synovial fluid is to provide nourishment and lubrication of the avascular structures to the TMJ. An articular disc divides the space into an upper and lower compartment. The muscles of mastication govern the movement of the mandible. The function of the articular disc is to separate forces resulting from movement.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 1 a. Whiplash injury b. Assault c. Surgery d. Clenching

10. Trauma affecting the TMJ is classified as direct, indirect, and secondary to parafunctional habits. Which is an example of a parafunctional habit?

ANS: D

Clenching and bruxism are examples of parafunctional habits affecting the TMJ. Whiplash injury is an example of indirect trauma to the TMJ. Assault is an example of direct trauma to the TMJ. Surgery is not an example or direct trauma, indirect trauma, or parafunctional habits.

REF: Pathophysiology of Temporomandibular Disorders, page 309

OBJ: 4

11. The most common systemic conditions that affect the TMJ are a. Sjögren syndrome and scleroderma. b. rheumatoid arthritis and juvenile rheumatoid arthritis. c. gout and Reiter syndrome. d. ankylosing spondylitis and mixed connective tissue disease.

ANS: B

Rheumatoid arthritis and juvenile rheumatoid arthritis are the most common systemic conditions that affect the TMJ. Sjögren syndrome and scleroderma are less likely to affect the TMJ than are rheumatoid arthritis and juvenile rheumatoid arthritis. Gout and Reiter syndrome are less likely to affect the TMJ than are rheumatoid arthritis and juvenile rheumatoid arthritis. Ankylosing spondylitis and mixed connective tissue disease are less likely to affect the TMJ than are rheumatoid arthritis and juvenile rheumatoid arthritis.

REF: Pathophysiology of Temporomandibular Disorders, page 309

OBJ: 4 a. Both statements are true. b. Both statements are false. c. The first statement is true; the second is false. d. The first statement is false; the second is true.

12. Temporomandibular dysfunction (TMD) can be caused by disorders of the muscles of mastication or by internal derangements of the components of the joint. Three cardinal features that suggest TMD include orofacial pain, joint noise, and restricted jaw function.

ANS: A

Both statements are true. TMD can be caused by disorders of the muscles of mastication or by internal derangements of the components of the joint. Three cardinal features that suggest a TMD include orofacial pain, joint noise, and restricted jaw function.

REF: Evaluation of Temporomandibular Disorders, page 309 OBJ: 4 | 5

13. Tenderness over the lateral pole of the condyle is indicative of a. crepitus. b. capsulitis. c. trismus. d. auscultation.

ANS: B

Capsulitis is tenderness over the lateral pole of the condyle. Crepitus is a dry crackling sound; tenderness over the lateral pole of the condyle is not indicative of crepitus. Trismus is the inability to fully open the mouth. Auscultation refers to listening to sounds within the body, using a stethoscope.

REF: Clinical Examination, page 309 OBJ: 4 a. Gastrointestinal b. Cardiovascular c. Psychiatric d. Arthritis

14. Caution is recommended with long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) because of what complications?

ANS: B

Caution is recommended with long-term use of NSAIDs because of cardiovascular complications. No direct correlation exists between long-term use of NSAIDs and gastrointestinal complications. There is no direct correlation between long-term use of NSAIDs and psychiatric complications. There is no direct correlation between long-term use of NSAIDs and arthritic complications.

REF: Nonsurgical Treatment, page 313 OBJ: 8 a. Osteoblastoma b. Synovial chondromatosis c. Osteoma d. Chondroblastoma

15. All are benign tumors that arise in the condyle except one. Which is the exception?

ANS: B

Synovial chondromatosis is the most common benign neoplasm of the synovium, not the condyle. The three most common benign tumors of the condyle are the osteoblastoma, osteoma, and chondroblastoma.

REF: Neoplasia, page 313 OBJ: 9 a. Panoramic imaging b. Transcranial imaging c. Computerized tomography (CT) d. Magnetic resonance imaging (MRI)

16. Which dental radiographic imaging is best for identifying bone abnormalities such as osteophytes, condylar erosion, fractures, ankylosis, and condylar hyperplasia?

ANS: C

CT is the most accurate for identifying bone abnormalities such as osteophytes, condylar erosion, fractures, ankylosis, and condylar hyperplasia. Panoramic imaging radiographs are limited to identifying gross changes in bone. Transcranial imaging radiographs are limited to identifying gross changes in bone. MRI is used for examining disc position, function, and form and the presence of joint effusions.

REF: Imaging, page 310

OBJ: 6

17. Hypermobility in which the patient is able to relocate the mandible back into the glenoid fossa is referred to as a. subluxation. b. dislocation. c. ankylosis. d. myofascial pain.

ANS: A

Subluxation refers to hypermobility in which the patient is able to relocate the mandible back into the glenoid fossa. Dislocation occurs when one or both of the condyles translate anterior to the articular eminence, resulting in an open lock that the patient cannot reduce. Ankylosis of the TMJ is defined as immobility of the condyle because of fibrous or bony union between the articulating structures of the joint. Myofascial pain is characterized as a dysfunctional muscle hyperactivity with regional pain, tenderness of the affected muscles, and variable amounts of reduced opening and complaints of malocclusion.

REF: Hypermobility Disorders, page 312

OBJ: 7 a. rotational and translational b. opening c. closing d. maximal interdigitation

18. The TMJ exhibits ginglymoarthrodial, or __________, movement.

ANS: A

The TMJ exhibits ginglymoarthrodial, or rotational and translational, movement. Translational movement occurs in the upper compartment, whereas the lower compartment functions primarily as the hinge or rotational component. The first phase of opening movement is characterized by rotational movement of the condyle followed by anterior translation to approximately the anterior peak of the articular eminence. The opening is accomplished mainly by the lateral pterygoid muscle, with some help from the anterior digastric muscle. The masseter, medial pterygoid, and temporalis are elevator muscles that close the mandible when activated. The point of maximal interdigitation is called centric occlusion.

REF: Anatomy of the Temporomandibular Joint, page 307

OBJ: 1 a. medial pterygoid b. lateral pterygoid c. masseter d. temporalis

19. Opening, or depressor function, of the mandible is accomplished primarily by the _____________ muscle.

ANS: B

Opening, or depressor function, of the mandible is accomplished primarily by the lateral pterygoid muscle with some help from the anterior digastric muscle. The medial pterygoid is an elevator muscle that closes the mandible when activated. The masseter is an elevator muscle that closes the mandible when activated. The temporalis is an elevator muscle that closes the mandible when activated.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 2 a. 90; 10 b. 75; 13 c. 50; 10 d. 25; 5

20. While up to _____% of the adult population has at least one sign and/or symptom of a temporomandibular disorder (TMD), most studies suggest that clinically significant TMDrelated jaw pain, dysfunction, or both affects about _____% of the general population.

ANS: B

Although up to 75% of the adult population has at least one sign and/or symptom of a temporomandibular disorder, most studies suggest that clinically significant TMD-related jaw pain, dysfunction, or both affects about 13% of the general population. Significantly more frequent and more severe TMD signs and symptoms are seen in women than in men and older adults. Although up to 75%, not 90%, of the adult population has at least one sign and/or symptom of a temporomandibular disorder, most studies suggest that clinically significant TMD-related jaw pain, dysfunction, or both affects about 5% rather than 10% of the general population. Although up to 75% and not 50% of the adult population has at least one sign and/ or symptom of a temporomandibular disorder, most studies suggest that clinically significant TMD-related jaw pain, dysfunction, or both affects about 5% rather than 10% of the general population. Although up to 75% and not 25% of the adult population has at least one sign and/ or symptom of a temporomandibular disorder, most studies suggest that clinically significant TMD-related jaw pain, dysfunction, or both affects about 5% of the general population.

REF: Epidemiology of Temporomandibular Disorders, page 309 OBJ: 5 a. Fibrotic intraarticular b. Bony intraarticular c. Fibrotic extraarticular d. Bony extraarticular

21. ____________ ankylosis is the most common type seen in the TMJ.

ANS: A

Fibrotic intraarticular ankylosis is the most common type seen in the TMJ. Ankylosis of the TMJ is defined as immobility of the condyle because of fibrous or bony union between the articulating structures of the joint. Ankylosis can be classified by tissue type (fibrous, bony), location (intraarticular, extraarticular), and extent of fusion (complete, incomplete). Fibrotic intraarticular ankylosis rather than bony intraarticular ankylosis is the most common type seen in the TMJ. Fibrotic intraarticular ankylosis rather than fibrotic extraarticular ankylosis is the most common type seen in the TMJ. Fibrotic intraarticular ankylosis rather than bony extraarticular ankylosis is the most common type seen in the TMJ.

REF: Ankylosis, page 313 OBJ: 7 a. 10 b. 30 c. 50 d. 70

22. About _____% of all TMJ ankylosis cases result from joint infection, usually after trauma.

ANS: C

About 50% of all TMJ ankylosis cases result from joint infection, usually after trauma, but 30% result from trauma without infection. About 50% rather than 10% of all TMJ ankylosis cases result from joint infection, usually after trauma. About 50% rather than 30% of all TMJ ankylosis cases result from joint infection, usually after trauma. About 50% rather than 70% of all TMJ ankylosis cases result from joint infection, usually after trauma.

REF: Ankylosis, page 313 OBJ: 7 a. more; more b. more; less c. less; more d. less; less

23. Children are _____ prone to TMJ ankylosis than adults because of greater osteogenic potential and _____ development of the joint meniscus.

ANS: B

Children are more prone to TMJ ankylosis than adults because of greater osteogenic potential and less development of the joint meniscus. Children are more prone to TMJ ankylosis than adults because of greater osteogenic potential and less rather than more development of the joint meniscus. Children are more rather than less prone to TMJ ankylosis than adults because of greater osteogenic potential and less rather than more development of the joint meniscus. Children are more rather than less prone to TMJ ankylosis than adults because of greater osteogenic potential and less development of the joint meniscus.

REF: Ankylosis, page 313 OBJ: 7 a. arthrocentesis b. arthroscopy c. condylotomy d. open joint surgery

24. Of the various surgical techniques used to treat TMDs, __________ involves surgical repositioning of the condyle.

ANS: C

Of the various surgical techniques used to treat TMDs, condylotomy involves surgical repositioning of the condyle. Arthrocentesis involves lavaging the joint through a needle. Arthroscopy allows direct visualization and manipulation of the joint. Open joint surgery is used to perform disc repositioning, replacement or excision, and total joint reconstruction using a prosthetic device or autogenous graft.

REF: Surgical Treatment, page 314 OBJ: 8 a. osteoblastoma b. chondroblastoma c. osteoma d. chondromatosis

25. Synovial _____________ is the most common benign neoplasm of the synovium.

ANS: D

Synovial chondromatosis is the most common benign neoplasm of the synovium. It is characterized by the development of metaplastic, highly cellular cartilaginous foci in the synovial membrane that results in degenerative changes consistent with osteoarthritis. It is characterized by swelling, pain, and limitation of movement. Synovial chondromatosis and not osteoblastoma is the most common benign neoplasm of the synovium. Synovial chondromatosis and not chondroblastoma is the most common benign neoplasm of the synovium. Synovial chondromatosis and not osteoma is the most common benign neoplasm of the synovium.

REF: Neoplasia, page 313 OBJ: 9

26. The three elevator muscles of mastication that when activated, close the mandible, include the masseter, the medial pterygoid, and the a. lateral pterygoid b. temporalis c. anterior digastric d. mylohyoid

ANS: B

The temporalis muscle is one of the three elevator muscles of mastication that close the mandible. The lateral pterygoid muscle opens, or depresses, the mandible. The anterior digastric muscle opens, or depresses, the mandible. The mylohyoid muscle opens, or depresses, the mandible.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 2 a. Trismus b. Articulation c. Fusion d. Crepitus

27. Which term describes the inability to fully open the mouth?

ANS: A

Trismus is defined as the inability to fully open the mouth. Articulation is another term for joint. Fusion refers to the union of two adjoining tooth germs. Crepitus is the dry, crackling sound that may be associated with the temporomandibular (TMJ) joint.

REF: Vocabulary, page 305 OBJ: 2 a. Zygomatic process b. Sphenoid bone c. Glenoid fossa of the temporal bone d. Occipital bone

28. The TMJ is the articulation between the mandibular condyle and which other structure?

ANS: C

The TMJ is the articulation between the condyle of the mandible and the glenoid fossa of the temporal bone. The zygomatic process is a portion of the maxilla. The sphenoid bone is a bone of the neurocranium, which sits in front of the temporal and occipital bones. The occipital bone is situated at the back and lower part of the skull.

REF: Anatomy of the Temporomandibular Joint, page 306 OBJ: 1 a. Temporalis b. Lateral pterygoid c. Masseter d. Medial pterygoid

29. Which muscle of mastication is most superior in its location?

ANS: A

The temporalis muscle is a broad muscle that covers much of the temporal bone and is superior in location when compared to the other muscles of mastication. The lateral pterygoid is more inferior in location compared to the temporalis muscle, functioning to open the mandible. The masseter muscle is inferior to the temporalis muscle, functioning to close the mandible. The medial pterygoid is found on the medial side of the lateral pterygoid plate, functioning to close the mandible.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 2 a. Temporalis b. Medial pterygoid c. Masseter d. Lateral pterygoid

30. Which muscle of mastication is responsible for opening the mandible?

ANS: D

The function of the lateral pterygoid muscle is the opening of the mandible. The function of the temporalis muscle is to close the mandible. The function of the medial pterygoid muscle is to close the mandible. The function of the masseter muscle is to close the mandible.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 2 a. Children b. Females, age 20–40 c. Males, age 40 d. Senior citizens

31. What is the demographic group that typically presents with temporomandibular disorders (TMD)?

ANS: B

The majority of patients with TMDs are female aged between 20 and 40 years. Children do not typically present with TMDs. Up to 75% of the population has at least one sign of TMD, and the majority of patients are younger females. Senior citizens are not reported to demonstrate a high incidence of TMD.

REF: Epidemiology of Temporomandibular Disorders, page 309

OBJ: 4 a. Stress b. Trauma c. Malocclusion d. Third molar extractions

32. What is the most likely cause of TMD?

ANS: B

Trauma has been suggested as the most likely cause of TMDs. Stress has been implicated in masticatory muscle pain, yet it is not considered the most likely cause of TMDs. Although it is a condition to be addressed, malocclusion is not the primary cause of TMDs. Sufficient evidence is not present to suggest that oral surgery procedures (such as third molar extraction) can cause TMDs.

REF: Pathophysiology of Temporomandibular Disorders, page 309

OBJ: 4 a. Lupus b. Gout c. Arthritis d. Scleroderma

33. What is the most common systemic condition that may affect the TMJ?

ANS: C

The most common systemic conditions that may affect the TMJ are rheumatoid arthritis and juvenile rheumatoid arthritis. Less common systemic diseases that may affect the TMJ include systemic lupus erythematosus. Less common systemic diseases that may affect the TMJ include gout. Less common systemic diseases that may affect the TMJ include scleroderma.

REF: Pathophysiology of Temporomandibular Disorders, page 309

OBJ: 5 a. Restricted jaw function b. Orofacial pain c. Previous dental surgery d. Joint noise

34. Three cardinal features for TMD include all except one. Which is the exception?

ANS: C

A history of previous dental surgery is not considered a cardinal feature of TMD. Three cardinal features suggest a TMD, and restricted jaw function is one of the three. Three cardinal features suggest a TMD, and orofacial pain is one of the three. Three cardinal features suggest a TMD, and joint noise is one of the three.

REF: Evaluation of Temporomandibular Disorders, page 309 OBJ: 3 a. Set the patient up slowly after the appointment. b. Maintain a shorter appointment time. c. Schedule the patient the first time of the day. d. Avoid loud background music in the office.

35. During a dental appointment, dental hygienists can help a patient with TMD by doing which procedure?

ANS: B

Keeping a shorter appointment time allows the patient time to relax in keeping their mouth open. Setting the patient up slowly may aid with persons with hypertension. Scheduling the patient with the first appointment of the day does not help patients with TMD. Avoiding loud background music has no effect on patients with TMD.

REF: Evaluation of Temporomandibular Disorders, page 309 OBJ: 4 a. MRI b. CBCT c. Panoramic imaging d. Arthrography

36. From the choices below, which type of radiographic imaging would be least helpful in diagnosing TMJ disease?

ANS: C

Of the choices listed, panoramic imaging is limited to identifying gross changes in bone, which is not often seen until a significant volume of destruction has occurred. MRI is mandatory for examining disc position, function, and morphology. CBCT is advantageous because of its accessibility, higher spatial resolution, reduced radiation exposure, and faster imaging. Arthrography uses a radiopaque contrast agent that is injected into the joint and may be useful when MRI is not tolerated and information about the position and morphology of the disc is needed.

REF: Imaging, pages 310-311 OBJ: 6 a. Both statements are true. b. Both statements are false. c. The first statement is true; the second statement is false. d. The first statement is false; the second statement is true.

37. Tumors arising in the TMJ area are common. The most common benign tumors that arise in the condyle include the osteochondroma.

ANS: D

Tumors arising in the TMJ area are rare. The most common benign tumors that arise in the condyle include the osteochondroma, osteoblastoma, chondroblastoma, and osteoma. Tumors arising in the TMJ area are rare. The most common benign tumors that arise in the condyle include the osteochondroma. The first statement is false; the second statement is true.

REF: Neoplasia, page 313

OBJ: 9 a. Dislocation b. Degenerative c. Displacement d. Odontogenic

38. Which term describes the condition where one or both of the condyles translate anterior to the articular eminence, resulting in an open lock that the patient cannot reduce?

ANS: A

Dislocation occurs when one or both of the condyles translate anterior to the articular eminence, resulting in an open lock that the patient cannot reduce. Degenerative denotes a progressive or irreversible deterioration. Displacement signifies moving something from its place or position. Odontogenic refers to arising from tooth-forming tissues.

REF: Hypermobility Disorders, page 312

OBJ: 4 a. <10% b. 20–30% c. 50–75% d. Nearly 100%

39. Approximately what percentage of persons with rheumatoid arthritis will have involvement of the TMJ?

ANS: C

Rheumatoid arthritis is an inflammatory autoimmune disorder of the joints. Approximately 50–75% of patients with rheumatoid arthritis have involvement of the TMJ during the course of the disease.

REF: Arthritis, page 312

OBJ: 4 a. Sign b. Symptom c. Iatrogenic d. Auscultation

40. Which term describes a procedure induced inadvertently by a health care provider or by medical treatment or a diagnostic procedure?

ANS: C

Iatrogenic is a term to describe the inadvertent induction by a health care provider or by medical treatment or diagnostic procedure. Iatrogenic causes of TMDs include the indiscriminate use of corticosteroid injection into the joint. A sign refers to objective evidence of disease that can be observed by a health care provider rather than by the patient. A symptom refers to subjective evidence of disease or a physical disorder that is observed by the patient. Auscultation is listening to sounds within the body.

REF: Vocabulary, page 304 OBJ: 2 a. To provide nourishment and lubrication of avascular structures b. To allow the bones to fit together properly c. To absorb shock d. To allow for correct palpation of the joint area

41. What is the function of the synovial fluid inside the joint?

ANS: A

The synovial fluid is produced by the synovial membrane that lines the joint. The fluid provides nourishment and lubrication of the avascular structures. The synovial fluid does not have an affect on the bones of the TMJ. The synovial fluid does not absorb shock to the joint. The synovial fluid does not allow for correct palpation of the joint area.

REF: Anatomy of the Temporomandibular Joint, page 307 OBJ: 2

Matching

For each vocabulary word below, select the corresponding definition from the list provided.

a. Method for evaluating and manipulating a joint via the insertion of a camera and instruments b. Dry, crackling sound c. Surgical puncture of a joint followed by lavage of joint space d. Physical examination using pressure of the hand or fingers e. Inability to fully open the mouth f. Radiography of a joint after injection of opaque contrast material g. Noninvasive diagnostic technique that uses radio waves to produce computerized images of internal body tissues h. Listening to sounds within the body, using a stethoscope i. Subjective evidence of disease or a physical disorder that is observed by the patient j. Objective evidence of disease that can be observed by a health care provider rather than by the patient k. Joint l. Induced inadvertently by a medical or dental care provider or by medical treatment or a diagnostic procedure