Dentin nbde part 2 sample by DENTIN

dentin™ | NBDE II

COPYRIGHT ©2015. DENTIN, LLC. ALL RIGHTS RESERVED. No part of this book may be produced, stored in a retrieval system, or transmitted in any form, or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission from the publisher. Produced by DENTIN, LLC dentin.co Printed in the United States

dentin™ | NBDE II

TABLE OF CONTENTS CHAPTER 1 ORAL PATHOLOGY METABOLIC & GENETIC DISEASES .................................................................................................... 8 INFLAMMATORY JAW LESIONS ....................................................................................................... 14 CONNECTIVE TISSUE LESIONS ........................................................................................................ 16 BENIGN EPITHELIAL TUMORS ......................................................................................................... 20 VERRUCAL PAPILLARY LESIONS ..................................................................................................... 22 NEOPLASMS ...................................................................................................................................... 23 ODONTOGENIC ABNORMALITIES .................................................................................................... 32 WHITE LESIONS ................................................................................................................................. 39 BLOOD DISEASES ............................................................................................................................. 46 NEUROLOGIC & MUSCLE DISORDERS ............................................................................................ 52 NON-ODONTOGENIC CYSTS ........................................................................................................... 54 ODONTOGENIC CYSTS ..................................................................................................................... 56 NON-ODONTOGENIC TUMORS ........................................................................................................ 59 ODONTOGENIC TUMORS ................................................................................................................. 65 PIGMENTED LESIONS ....................................................................................................................... 71 RED-BLUE LESION ............................................................................................................................ 74 PSEUDOCYSTS (NO EPITHELIAL LINING ......................................................................................... 76 SALIVARY GLAND TUMORS ............................................................................................................. 77 MALIGNANT SALIVARY GLAND TUMORS ........................................................................................ 80 ULCERATIVE CONDITIONS ............................................................................................................... 84 VESICULO-BULLOUS DISEASES ...................................................................................................... 88 ORAL PATHOLOGY TEST PEARLS ................................................................................................... 96 RADIOGRAPHIC PATHOLOGY ........................................................................................................ 101

CHAPTER 2 RADIOLOGY OSTEONECROSIS ............................................................................................................................ 108 DIGITAL RADIOGRAPHY .................................................................................................................. 109 SECONDARY RADITION, COLLIMNATION, FILTRATION ............................................................... 110 RADIATION ....................................................................................................................................... 111 PANORAMIC & CONE BEAM ........................................................................................................... 113 CEPHALOMETRICS & BWX ............................................................................................................. 114 SUBMENTAL-VERTICAL .................................................................................................................. 115 WATER’S VIEW................................................................................................................................. 116 TOWNE’S VIEW ................................................................................................................................ 117 CHEMICALS, SOLUTION, & DEVELOPING ERRORS ...................................................................... 118 RADIOGRAPHIC TECHNIQUES & ERRORS .................................................................................... 120

dentin™ | NBDE II

CHAPTER 3 DENTAL EMERGENCY PROTOCOL & MEDICALLY COMPROMISED CONSIDERATIONS DENTAL EMERGENCY PROTOCOL ................................................................................................ 127 MEDICALLY COMPROMISED CONSIDERATIONS ......................................................................... 129

CHAPTER 4 DENTAL PHARMACOLOGY ANTIBIOTIC PRE-MEDICATION GUIDELINES ................................................................................. 133 CENTRAL NERVOUS SYSTEM ........................................................................................................ 135 ADRENERGICS (SYMPATHETICS) .................................................................................................. 137 ADRENERGIC AGONISTS ................................................................................................................ 139 ANTI-ADRENERGICS (SYMPATHOLYTICS) .................................................................................... 143 CHOLINERGICS ............................................................................................................................... 147 ANTI-CHOLINERGICS ...................................................................................................................... 150 NICOTINIC RECEPTOR ANTAGONISTS .......................................................................................... 151 DRUG ADMINISTRATION ROUTES & METABOLISM ...................................................................... 152 DEA DRUG SCHEDULE ................................................................................................................... 156 ANESTHETICS .................................................................................................................................. 158 NITROUS OXIDE............................................................................................................................... 163 ANTI-ANXIETY AGENTS ................................................................................................................... 167 CARDIOVASCULAR AGENTS .......................................................................................................... 170 ANTI-DEPRESSANTS ....................................................................................................................... 178 ANTI-PSYCHOTICS .......................................................................................................................... 180 ANTI-HISTAMINES ........................................................................................................................... 181 ANTI-CONVULSANTS & ANTI-INFECTIVES .................................................................................... 183 ANTI-FUNGALS ................................................................................................................................ 197 ANTI-PROTOZOALS ......................................................................................................................... 198 ANTI-VIRALS .................................................................................................................................... 199 NSAIDS ............................................................................................................................................. 201 ACETAMINOPHEN & OPIODS ......................................................................................................... 207 ANTI-NEOPLASTIC (CANCER) DRUGS ........................................................................................... 216 HYPOGLYCEMICS ........................................................................................................................... 218

dentin™ | NBDE II

CHAPTER 5 PROSTHODONTICS REMOVABLE PARTIAL DENTURES ................................................................................................. 220 MANDIBULAR MAJOR CONNECTORS ........................................................................................... 221 MAXILLARY MAJOR CONNECTORS ............................................................................................... 224 INDIRECT RETAINERS ..................................................................................................................... 227 DIRECT RETAINERS......................................................................................................................... 230 RPD STRESS BREAKERS ................................................................................................................ 235 SURVEYING RPD ABUTMENTS ...................................................................................................... 237 COMPLETE DENTURES ................................................................................................................... 240 MANDIBULAR COMPLETE DENTURES .......................................................................................... 242 MAXILLARY COMPLETE DENTURES .............................................................................................. 244 ORAL PATHOLOGY & ILL-FITTING COMPLETE DENTURES ......................................................... 246 IMMEDIATE DENTURES .................................................................................................................. 248 OVERDENTURES & OCCLUSION .................................................................................................... 250 DENTURE TEETH SELECTION ........................................................................................................ 261 PHONETICS ..................................................................................................................................... 264 FIXED PARTIAL DENTURES (CROWN & BRIDGE) .......................................................................... 265 PORCELAIN SHADE SELECTION .................................................................................................... 268 PONTIC DESIGN .............................................................................................................................. 269 CANTILEVER BRIDGES & PIER ABUTMENTS ................................................................................. 271 MARYLAND BRIDGE ........................................................................................................................ 272 BRIDGES & BRIDGE ABUTMENTS .................................................................................................. 274 POST & CORES ................................................................................................................................ 276 PORCELAIN VENEERS..................................................................................................................... 278 IMPRESSION MATERIALS & CEMENT ............................................................................................ 279 DENTAL IMPLANTS ......................................................................................................................... 284

CHAPTER 6 OPERATIVE DENTISTRY DENTAL CEMENTS .......................................................................................................................... 291 PREPARATION BASES & CAVITY LINERS ...................................................................................... 295 CARIES ............................................................................................................................................. 298 GOLD ................................................................................................................................................ 302 COMPOSITES .................................................................................................................................. 311 AMALGAM ........................................................................................................................................ 320 BIOMATERIALS ................................................................................................................................ 333 HAND INSTRUMENTS & BURS ....................................................................................................... 335 OPERATIVE TEST PEARLS .............................................................................................................. 339

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CHAPTER 7 PERIODONTICS PERIODONTIUM & FIBERS .............................................................................................................. 353 FLAPS, GRAFTS, & SURGERY ........................................................................................................ 358 GINGIVITIS........................................................................................................................................ 367 PERIODONTITIS ............................................................................................................................... 373 PLAQUE & CALCULUS .................................................................................................................... 379 SCALING, ROOT PLANING, & GINGIVAL CURETTAGE .................................................................. 386 OCCLUSAL TRAUMA ....................................................................................................................... 393 ABSCESSES ..................................................................................................................................... 396 ORAL HYGIENE INSTRUCTION ....................................................................................................... 397

CHAPTER 8 ORAL SURGERY NERVE ANATOMY ............................................................................................................................ 403 ARTERIES & GLANDS ...................................................................................................................... 407 MASTICATION MUSCLES & TMJ .................................................................................................... 411 FRACTURES ..................................................................................................................................... 415 ANESTHESIA .................................................................................................................................... 420 EXODONTIA...................................................................................................................................... 434 GRAFTS ............................................................................................................................................ 444 BIOPSY ............................................................................................................................................. 447 DISORDERS & CONDITIONS ........................................................................................................... 449 CPR GUIDELINES ............................................................................................................................ 454 HORMONES, CALCIUM, BLOOD GLUCOSE .................................................................................. 457

CHAPTER 9 ENDODONTICS ROOT FRACTURES .......................................................................................................................... 463 FLAPS & SLOB RULE ....................................................................................................................... 464 PULPOTOMY & APEXIFICATION ..................................................................................................... 466 DIRECT & INDIRECT PULP CAPPING ............................................................................................. 467 CANAL ACCESS & DEBRIDEMENT ................................................................................................. 468 OBTURATION ................................................................................................................................... 469 IRRIGANTS & CHELATING AGENTS ............................................................................................... 470 ZOE, MTA, APICOECTOMY ............................................................................................................. 471 PERIRADICULAR SURGERY & CURETTAGE .................................................................................. 472 ENDODONTIC INSTRUMENTATION ................................................................................................ 473 MANAGING AVULSION INJURIES ................................................................................................... 474 EXTERNAL & INTERNAL RESORPTION........................................................................................... 475 PULP & DENTIN ............................................................................................................................... 477 MANDIBULAR & MAXILLARY ROOT ANATOMY ............................................................................. 478 RCT ADJUNCTS, CONTRAINDICATIONS & INDICATIONS ............................................................. 481 PERIAPICAL & PERIODONTAL ABSCESSES .................................................................................. 483 PROBING LESIONS.......................................................................................................................... 485 REVERSIBLE & IRREVERSIBLE PULPITIES, NECROSIS ................................................................ 485 RESTORING TEETH AFTER RCT ..................................................................................................... 487 5

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CHAPTER 10 PEDIATRIC DENTISTRY ANTI-ANXIETY MEDICATIONS......................................................................................................... 489 PULP TREATMENT........................................................................................................................... 491 DISEASES & CONDITIONS .............................................................................................................. 494 TOOTH ABNORMALITIES ................................................................................................................ 503 TOOTH DEVELOPMENT & ERUPTION ............................................................................................ 505 PRIMARY DENTITION ...................................................................................................................... 509 FLUORIDE ........................................................................................................................................ 512 SEALANTS ........................................................................................................................................ 517 TOOTH TRAUMA .............................................................................................................................. 522 BEHAVIOR MANAGEMENT .............................................................................................................. 526

CHAPTER 11 ORTHODONTICS OVERBITE & OVERJET ..................................................................................................................... 529 MALOCCLUSION ............................................................................................................................. 530 ANGLE MALOCCLUSION CLASSIFICATION ................................................................................... 531 CROSSBITES ................................................................................................................................... 534 CEPHALOMETRICS ......................................................................................................................... 536 MIXED DENTITION & ANALYSIS ...................................................................................................... 538 SUPERNUMERARY TEETH & SPACE MAINTENANCE ................................................................... 541 ORTHODONTIC APPLIANCES ......................................................................................................... 544

CHAPTER 11 BEHAVIORAL SCIENCE, PUBLIC HEALTH, OSHA & INFECTION CONTROL BEHAVORIAL SCIENCE ................................................................................................................... 553 OSHA ................................................................................................................................................ 558 PUBLIC HEALTH .............................................................................................................................. 564 INFECTION CONTROL ..................................................................................................................... 569

dentin™ | NBDE II

ORAL PATHOLOGY & DISEASES METABOLIC & GENETIC DISEASES HYPERTHYROIDISM-caused by excessive production of thyroid hormone (THYROXIN). Thyroxin’s stimulates cellular metabolism, growth, and differentiation of all tissues. In excess, it leads to high basal metabolism, fatigue, weight loss, excitability, elevated temperature (heat intolerance, sweating), generalized osteoporosis, fine hair, diarrhea, tremor (shakiness), tachycardia (rapid heart rate). Oral manifestations are not uncommon, but if the disturbance starts early in life, premature tooth eruption and loss of deciduous dentition are common. GRAVES DISEASE & EXOPTHALMOS (bulging eyes). Two types of Hyperthyroidism: 1. Graves Disease (Toxic Diffuse Goiter)-most common form that occurs mostly in WOMEN ages 20-40. Usually arises after an infection or physical or emotional stress. Typical signs of hyperthyroidism are present plus GOITER (bulging neck) & EXOPHTHALMOS (bulging eyes). 2. Plummer’s Disease (Toxic Multinodular Goiter)-caused by the presence of many toxic thyroid nodules (adenomas) within the thyroid gland. Plummer’s is uncommon in adolescents and young adults, and increases with age. Exophthalmos (bulging eyes) is rare.

HYPOTHYROIDISM-a clinical feature is WEIGHT GAIN, cold intolerance, lowered pitch of voice, mental and physical slowness, constipation, dry skin, coarse hair, and puffiness of face, eyelids, and hands. •

Myxedema-very severe hypothyroidism in adults, much more common in WOMEN than men. Characterized by puffiness of face and eyelids, swelling of tongue and larynx. Skin becomes dry, and rough, and hair sparse. Individual has a low basal-metabolic rate and low body temperature, poor muscle tone, low strength, tires easily, and are mentally sluggish. Myxedema is alleviated by administering thyroid hormones

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Cretinism-severe hypothyroidism in a child, due to lack of thyroid hormone causing retardation of growth and abnormal bone development. Severe mental retardation is caused by improper CNS development. If recognized early, Cretinism can be improved with thyroid hormones.

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Dental findings in a child with hypothyroidism are a LARGE TONGUE, under-developed mandible, over-developed maxilla, delayed teeth eruption, and longer retained deciduous teeth.

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HYPERPARATHYROIDISM-a common complication is KIDNEY STONES (renal calculi). Kidney stones form due to an increase in urinary excretion of calcium and phosphate. Osteoporosis, GIANT CELL GRANULOMAS, and metastatic calcifications are manifestations of hyperparathyroidism. 8

dentin™ | NBDE II PAGET’S DISEASE (ENLARGED ALVEOLAR RIDGES)

OSTEOMALACIA (Adult Rickets) – SOFTENING of bones in adults because osteoid tissue in bones failed to calcify due to LACK OF VITAMIN D. More common in women, and may be asymptomatic until a bone fracture occurs. •

Steatorrhea-one of the most common causes of Osteomalacia due to FAT MALABSORPTION where the body cannot absorb fats, so fats are passed directly out of the body in stool causing poor absorption of vitamin D (fat soluble) and calcium. Osteomalacia affects ALL BONES, specifically at their epiphyseal growth plates.

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Signs & Symptoms: pain in bones of the arms, legs, spine, and pelvis.

RICKETS (Child Osteomalacia) –causing skeletal deformities, and usually accompanied by irritability and generalized muscle weakness. Bowlegs, pigeon breast, and protruding stomach are signs. Teeth are affected by delayed eruption, malocclusion, and developmental abnormalities of dentin and enamel, with a higher caries rate. CEREBRAL PALSY – a group of disorders affecting body movement and muscle coordination due to an insult or anomaly of the brain’s motor control centers. This damage interferes with messages from brain to the rest of the body. The effects vary greatly among people. •

CP is mainly characterized by SPASTIC PARALYSIS or impairment of control or coordination over voluntary muscles. Often accompanied by mental retardation, seizures, & disorders of vision/communication.

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NO ORAL PATHOLOGIC MANIFESTATIONS are present in people with cerebral palsy, but several conditions are more common, or more severe than in the normal population: Ø Higher incidence of periodontal disease, caries, bruxism, and malocclusion. Ø Prone to gingival hyperplasia if Dilantin is used to control seizures. Ø More susceptible to trauma, especially maxillary anterior teeth.

DOWN SYNDROME – a congenital defect caused by a chromosomal abnormality (TRISOMY 21), marked by various degrees of mental retardation and characteristic physical features (short, flattened skull, slanting eyes, thickened tongue/fissured, broad hands/feet, etc.) •

Oral Manifestations: mandibular prognathism, increased periodontal disease, thickened or fissured tongue, delayed teeth eruption, higher incidence of congenitally missing teeth, malocclusion, & enamel dysplasia.

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RADIOLOGY Radiographs show shading from black to white (most radiolucent to most radiopaque). From least to most radiopaque: (PDL space, dentin, enamel, ZOE, and amalgam). Radiopaque Structures & Dense Materials: metals, enamel, dentin, and bone that INHIBIT the passage of x-rays and appear WHITE on the processed film. Less radiation penetrates the structure and reaches the film. Radiolucent Structures and Materials: less dense materials like soft tissue and air space that appear gray to black on processed film) ALLOWING RADIATION to pass through by absorbing very little radiation. More radiation penetrates the structure and reaches the film. § Radiolucent Lesions-appear every time bone is DESTROYED. Unilocular & Multilocular are terms only used to describe radiolucent lesions. 1. well-defined unilocular (one cavity): border is well-defined. Most benign lesions are unilocular, well-defined. 2. well-defined multilocular: border is well-defined with several cavities. 3. well-defined honeycomb or soap bubble (multilocular): 4. diffuse-cannot follow the border of the radiolucency: 90% of the time it is cancer. If loss of cortical plates, the first diagnosis is cancer. OSTEORADIONECROSIS-the necrosis of bone produced by ionizing radiation that is more common in the MANDIBLE than maxilla due to the richer vascular supply to the maxilla, and because the mandible is more often irradiated. The most common factors precipitating osteoradionecrosis are pre-irradiation & post-irradiation extractions, and periodontal disease. Damage to blood vessels (not nerves or muscles) predisposes a patient to developing osteoradionecrosis. A complications that can occur with patients taking IV Bisphosphonates or oral bisphosphonates for more than three years orally (i.e. Fosamax). Osteoradionecrosis is more common IN THE MANDIBLE probably because of the richer vascular supply to the maxilla and the fact that the mandible is more frequently irradiated. Caution with patients on IV bisphosphonates or if taking oral bisphosphonates (i.e. Fosamax). • May occur after dental extractions. • The most common factors precipitating osteoradionecrosis are pre and post irradiation extractions and periodontal disease. OSTEONECROSIS

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dentin™ | NBDE II TOWNE’S VIEW-the best film to visualize the CONDYLES & NECK OF MANDIBLE from an AP projection. The patient lies on his back with the film under his head. The x-ray source is from the front, but is rotated 30° from the Frankfort plane and is directed right at the condyles. • Towne’s view is often of value to assess the status of the condyles, condylar neck, and rami because superimposition of the mastoid and zygoma over the condylar neck region in the straight postero-anterior projection often makes interpretation difficult. Towne’s view eliminates this superimposition to give good visualization of the condylar area and rami. •

Reverse Towne’s View-used to identify fractures of the condylar neck and ramus area. TOWNE’S VIEW

Conventional TMJ Radiographs: show the condyles position in the glenoid fossa, range of the condyles’ antero-posterior movement, and areas of bone destruction on the condylar heads. Developer Solution-a chemical solution that converts the invisible image on a film into a visible image composed of minute masses of black metallic silver. Its function is to reduce silver halide crystals to black metallic silver.

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dentin™ | NBDE II CERVICAL BURNOUT

Inverse Square Law = original intensity = new distance2 new intensity original distance2 Important: for a given beam of radiation, the intensity is INVERSELY proportional to the square of the distance from the radiation source. The intensity of an x-ray beam at a given point is dependent on the distance of the measuring device from the FOCAL SPOT. The reason for this decrease in intensity (the reason it is inversely proportional) is because the x-ray beam spreads out as it moves away from the source. The “spread out” beam is less intense. Focal Spot-the small area of tungsten on the anode (target) from which x-rays emanates and that receives the impact of the speeding electrons. Focal spot is 1 of 3 factors that influences image sharpness. The size of the x-ray tube focal spot influences radiographic DEFINITION. § Target (tungsten target)-a tungsten wafer embedded in the anode face at the point of electron bombardment. §

Target Film Distance (source-to-film distance)-distance from the x-ray source (the focal spot on the tungsten target) to the film. It is determined by the length of the cone (position-indicating device = PID). Two standard target-film distances are used in intra-oral radiography. 1. 20cm (8 inches): is the short cone that exposes more tissue by producing a more divergent beam. 2. 41cm (16 inches): is the long cone that reduces the amount of exposed tissue by producing a less divergent beam and a sharper image.

Half-Value Layer (HVL)-the amount of material required to reduce the intensity of an x-ray beam to half. For x-ray beams, this is normally expressed in aluminum or copper thickness, but may also be expressed in other materials or media (i.e. water). HVL is an indicator of the QUALITY of an x-ray beam. Half-value layer is strictly defined for different quantities: photon fluence (# of photons/cm2), energy fluence (# of photons x photon energy/cm2) or absorbed dose. Intensity-a term commonly used, but is too vague, thus is avoided.

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DENTAL EMERGENCY PROTOCOL ANAPHYLACTIC REACTION (allergic reaction develops in seconds or minutes) after local anesthetic, nitrous, or dental material exposure. LIFE-THREATENING causing BRONCHOSPAM & DROP IN B.P. (EPI pen bronchodilates and raises patient’s BP): 1. Call 911 and position the awake patient in a comfortable position. 2. Get the preloaded EPI syringe in the emergency kit and inject EPI pen into patient’s DELTOID, TONGUE, or LATERAL THIGH. 3. Re-administer EPI pen in 5 minutes ONLY IF SYMPTOMS PERSIST.

CHEST PAIN (ANGINA PECTORIS)—patient has tight, heavy, or constricted chest pain and may clench their fist against their chest. 1. Call 911 and position patient so he/she is comfortable and ask if they have their nitroglycerin tablets or spray on them. If not, give 2 sprays of NITROGLYCERIN (vasodilator) onto the patient’s tongue. 2. Dental treatment can continue if patient and doctor are comfortable. Important: do not give spray/tablets if the patient has chest pain and feels faint or dizzy (means BP is dropping), or if the patient took VIAGRA within 24hrs. ________________________________________________________________________ HEART ATTACK: after chest pain, patient says their pain is getting worse, patient has taken 3 doses of nitroglycerin at five minute intervals and pain continues, or the chest pain went away but comes back, or the patient has had no history of heart disease or chest pain. CRUSHING, INTENSE, RADIATING PAIN from the chest to the stomach or to the left side of the neck, jaw, left arm, and/or pinkie finger (tingles). SKIN TURNS ASHEN GRAY & PATIENT MAY SWEAT PROFUSELY. 1. Call 911 and position the patient so they are comfortable. 2. Administer 50% nitrous oxide & 50% oxygen (has same effect as IV Morphine) for pain and delivers more oxygen to the muscles/brain. 3. Give two sprays of nitroglycerin on patient’s tongue and have the patient CHEW 1 tablet of adult-dose ASPRIN (325mg) EXCEPT if patient is allergic to aspirin, has a bleeding disorder, or gastric/peptic ulcer. ASPIRIN prevents clot from getting bigger.

CARDIAC ARREST (UNCONSCIOUS PATIENT): 1. Call 911 while dentist lays the patient flat in dental chair with their feet ELEVATED. 2. (CAB): Dentist starts chest compressions, check airway and open with the HEAD LIFT/CHIN TILT and then check for breathing and carotid pulse (in the groove under and to the side of the Adam’s Apple). Follow CAB (compressions, airway, and breathing)-new AHA guideline. 3. Dentist gives CPR (30 chest compressions for every 2 breaths). 30:2 ratio.

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dentin™ | NBDE II DIABETIC SHOCK (HYPOGLYCEMIA = LOW BLOOD SUGAR). MENTAL CONFUSION, patient feels cold, sweaty, and shaky. •

Before treatment ask patient when did they take their insulin and eat last. If not recent, give patient third cup of ORANGE JUICE or NON-DIET SODA wait 5 minutes, then give another third cup. After 5 minutes, give last third cup. WITHIN 15 minutes signs should subside.

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Unconscious Diabetic: 1. CALL 911 and lay patient flat with feet raised, check airway (head tilt/chin lift), check breathing (look, listen, feel) and check carotid pulse. DO CPR if not breathing/no pulse (15 compressions for every 2 breaths). 15:2. 2. DO NOT ADMINSTER DRUGS!

SYNCOPE (FAINTING): can occur due to EMOTIONAL STRESS (nervousness). Occurs when there is a temporary decrease in blood flow to the brain due to sudden drop in BP, HR or blood volume change. Can happen to anyone, but the patient usually has an underlying medical condition like anemia or heart disease. Signs a patient may faint: light-headed, nausea, heart palpitations. 1. Lay patient in dental chair with legs ELEVATED. 2. Place a cold, wet towel over their forehead 3. Administer oxygen and AROMATIC AMMONIA held under patient’s nose to stimulate blood flow to brain via movement. SIEZURE (EPILEPSY): caused by signals in the brain are disrupted. GRAND-MAL is the most-common type (last 2-3 minutes; the body becomes rigid and relaxes). A seizure lasting more than 5 minutes is called Status Epilepticus and is life-threatening). Signs: patient may have a visual, sound, or smell aura immediately before seizure starts (so ask the patient with seizure history if they have a common aura or if they have taken their anti-epileptic medication. 1. Call 911. 2. Remove any sharp objects away from the patient and have one person gently hold the arms and the other the legs to protect patient from injury. Note: if a minor has a seizure, call the parent into the room to help.

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DENTAL PHARMACOLOGY ANTIBIOTIC PROPHYLAXIS GUIDELINES FOR DENTAL PROCEDURES TO PREVENT INFECTIVE ENDOCARDITIS 2007 AMERICAN HEART ASSOCIATION GUIDELINES Standard Regimen Amoxicillin: s Adults: 2g orally 1hr prior to appointment (4 capsules) s Children: 50mg/kg (not to exceed adult dose) orally 1hr before appointment

*1kg = 2.20 lbs 22 lb child can Rx 500mg 44 lb child can Rx 1000mg (1g) 66 lb child can Rx 1500mg (1.5g) 88 lb child or more can Rx adult dose

Penicillin Allergic Patients Clindamycin: s Adults: 600mg orally 1hr prior to appointment s Children: 20mg/kg orally 1hr prior to appointment s Each capsule is 300mg, so dispense 2 per appointment) Cephalexin: s Adults: 2g orally 1hr prior to appointment s Children: 50mg/kg orally 1hr prior to appointment s Each capsule is 500mg, so dispense 4 capsules per appointment) Cefadroxil: s Adults: 2g orally 1hr prior to appointment s Children: 50mg/kg orally 1hr prior to appointment s Each capsule if 500mg, so dispense 4 capsules per appointment. Azithromycin: s Adults: 500mg orally 1hr prior to appointment s Children: 15mg/kg orally 1hr prior to appointment Clarithromycin: s Adults: 500mg orally 1hr prior to appointment s Children: 15mg/kg 1hr prior to appointment

Bacterial Endocarditis Prophylaxis (Antibiotic Prophylaxis) is Recommended: 1. Prosthetic/Artificial Cardiac Valves (i.e. biosynthetic (mechanical) & homograft (pig) valves). 2. Previous Bacterial Endocarditis (infection of the heart lining or heart valves). 3. Congenital Heart Disease of: (unrepaired cyanotic congenital heart disease, including those with palliative shunts and conduits); Completely repaired congenital heart disease with prosthetic material or device placed surgically or via catheter during the first 6 months after the procedure; repaired congenital heart disease with residual defects at the site or adjacent to the site of a prosthetic patch or device (which inhibits endothelialization); cardiac transplantation recipients with cardiac valvular disease. Complex Cyanotic Congenital Heart Disease (i.e. single ventricle states, transposition of great arteries, Tetrology of Fallot). 4. Surgically constructed synthetic PULMONARY shunts or conduits. 5. Hypertrophic Cardiomyopathy.

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Nasal decongestant-α1 adrenergic agonist causes vasoconstrictor with Phenylephrine (NeoSynephrine).

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Bronchial relaxation/dilation & airway dilation (Asthma)-β 2 adrenergic agonist o Asthma-a respiratory disorder characterized by recurring episodes of paroxysmal dyspnea, wheezing on expiration, coughing, and viscous mucoid bronchial secretions. Asthma episodes may be precipitated by inhalation of allergens or pollutants, infection, vigorous exercise, or emotional stress. o

Bronchodilators (β 2 adrenergic agonists that treat an acute asthma attack): EPI, Albuterol (Proventil), Salmeterol (Serevent), & Metaproterenol (Alupent). These drugs stimulate beta receptors in the airway to cause bronchodilation, thus are used to help reverse an acute asthmatic attack. They are taken via aerosol, inhalers, and nebulizer.

Aminophylline-a THEOPHYLLINE compound administered orally as bronchodilators in reversible airway obstruction due to asthma or COPD (chronic obstructive pulmonary disease). Theophylline compounds RELAX bronchial smooth muscle to improve airway function. A CNS stimulant that treats asthma.

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Cardiac stimulation-β1 adrenergic agonist like Isoproterenol.

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Epinephrine (Adrenalin), Phenylephrine (Neo-Synephrine), Albuterol (Proventil; Ventolin), & Isoproternol are all adrenergic agonists the bind to adrenergic receptors.

2 Types of Adrenergic Agonists (Sympathomimetic Agents): 1. Direct-Acting Agonist: those drugs that interact with α or β receptors. Direct-acting adrenergic agonists can be receptor selective or receptor non-selective: § Phenylephrine (Neo-Synephrine): α1 selective agonist. A nasal decongestant, and mydriatic in ophthalmic preparations to treat chronic orthostatic hypotension, and in combination with local anesthetics to prevent anesthetic diffusion away from the injection site. 100x less potent than EPI, §

Clonidine (Catapres): α2 selective agonist. Used primarily as an anti-hypertensive agent.

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Dobutamine: β1 selective agonist.

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Terbutaline: β2 selective agonist administered orally, subcutaneously, or by inhalation. Primarily used in long-term treatment of obstructive airway diseases or emergency treatment of bronchospasm. Given parenterally in emergency treatment of status asthmaticus and to delay premature delivery.

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Albuterol: β2 selective agonist. Administered orally or by inhalation. Primarily used in longterm treatment of obstructive airway diseases, emergency treatment of bronchospasm, or to delay premature delivery.

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Epinephrine (Adrenaline): a vasoconstrictor and α 1,2 & β 1,2 direct acting agonist (stimulates 4 receptors). o Physiologic actions produced by EPI: • Constricts arteriolar blood vessels (vasoconstriction) via binding to α1 receptors. Alpha receptor stimulation causes a vasopressor response (↑BP). • Relaxes bronchial smooth muscle (bronchodilation) by binding to β2 receptors. Beta-receptor stimulation causes airway dilation and increased cardiac output.

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AMIDE PREPARATIONS & AVERAGE DURATION BY ROUTE AMIDE Mepivacaine (Carbocaine 3%) Prilocaine (Citanest Plain 4%) Prilocaine 4% with 1:200K EPI (Citanest Forte with EPI) Lidocaine 2% with 1:100K EPI Marcaine 0.5% with EPI (Bupivacaine with EPI 1:200K)

Local Infiltration 20 min 20 min 2.25 hrs 60 min 60 min

Inferior Alveolar Block 40 min 2.5 hrs 3.0 hrs 90 min 5-7 hrs

Local Anesthesia in Children: WEIGHT determines the maximum dose of a local anesthetic that can be administered in children. For Lidocaine (2%), a dosage of 4.4mg/kg is not exceeded (maximum adult dose of 300mg). MAX RECOMMENDED LIDOCAINE DOSES FOR CHILDREN Drug Lidocaine (2%) w/wo EPI Patient Weight (kg/lb) 10kg = 23lbs

Max Dose (mg/kg) 4.4mg/kg (300 mg max) Mg 44mg

Mg/Carpule 36mg = 1 Carpule # of Carpules 1.2

15kg = 34.5lbs 20kg = 46lbs 25kg =57.5lbs

66mg 1.8 88mg 2.4 100mg 2.6 *1 kg = 2.3lbs *2% = (20mg/ml) x (1.8ml)/1 carpule = 36mg/1 carpule A dental local anesthetic carpule contains 1.8ml of a 2% Lidocaine solution with 1:100,000 EPI. Thus, the carpule contains 36mg of Lidocaine and 0.018mg of EPI. § Important: 1mL of a 2% solution of Lidocaine with 1:100K EPI contains 20mg of Lidocaine and 0.010mg of EPI. § Important: 1 dental capule contains 1.8ml solution. Thus, 1.8ml of 2% Lidocaine solution with 1:100K EPI contains 36mg of Lidocaine and 0.018mg EPI. Maximum recommended adult dose of Lidocaine is 300mg. To reach this max level, 15ml of 2% Lidocaine is needed. Important: there are 20mg of Lidocaine in every 1ml of 2% Lidocaine. o 300mg/20mg = 15ml. o 20mg x 1.8ml (in every carpule) = 36mg per carpule. o 300mg/36mg = 8.3 carpules (8 carpules of 2% Lidocaine can be used). MAX RECOMMENDED DOSES OF LOCAL ANESTHETICS Drug Lidocaine (Xylocaine) Mepivacaine (Carbocaine) Prilocaine (Citanest) Bupivicaine (Marcaine)

Max mg 300mg 300mg 400mg 90mg

162

Max mL 15ml 10ml 10ml 18ml

Concentration % 2% 3% 4% 0.5%

# of Carpules 8.3 5.6 5.6 10

dentin™ | NBDE II

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MANDIBULAR RPD MAJOR CONNECTORS Basic cross-section form is HALF-PEAR SHAPED located above moving tissues but as far below the gingival margins as possible. To determine which mandibular major connector to use, measure from the height of the floor to the lingual gingival margins. 1. LINGUAL BAR: superior border must be at least 4mm below the gingival margins (tooth-tissue junction) to prevent plaque collection and margin inflammation. There must be at least 7mm of space/clearance between the gingival margin and mouth floor. HALF-PEAR SHAPED in crosssection. • Indication: Used when sufficient space exists between the slightly elevated alveolar lingual sulcus and lingual gingival tissues. Must be a minimum of 7mm vertical height between the gingival margin and mouth floor (inferior border of the bar). 3mm space between superior border of the bar and gingival margin + the bar must be 4mm wide = 7mm. •

Contraindication: when severely tipped premolars and molars are present, an alternate framework or crowns are recommended. LINGUAL BAR

SUBLINGUAL BAR: used when there is INSUFFICIENT SPACE for a lingual bar. HALF-PEAR SHAPED. • Used when the height of the mouth floor is < 6mm from the free gingival margins or when it is desirable to keep the free gingival margins of the remaining anterior teeth exposed, and there is inadequate depth of the mouth floor to place a lingual bar. • Its bulkiest portion is to the lingual and it’s tapered is toward the labial. • Bar’s superior border MUST be at least 3mm below the free gingival margin. • Bar’s inferior border is at the height of alveolar lingual sulcus when the patient’s tongue is slightly elevated. • Requires a FUNCTIONAL IMPRESSION. • Contraindication: remaining natural anterior teeth are severely lingually tilted. SUBLINGUAL BAR

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CINGULUM BAR (CONTINUOUS BAR): • Used when a lingual plate or sublingual bar is indicated, but the axial alignment of the anterior teeth is such that excessive blockout of inter-proximal undercuts is required. •

Contraindications: anterior teeth severely tilted lingually, wide diastemas between anterior teeth causing the metal cingulum bar to be displayed.

•

It’s a thin, narrow (3mm) strap located on the cingula of anterior teeth, scalloped to follow inter-proximal embrasures with its superior borders tapered to tooth surfaces. Originates bilaterally from rests of adjacent abutments. CINGULUM BAR

LINGUOPLATE: Indications: § High floor of the mouth (< 7mm vertical height) or high lingual frenum. Preferred over a lingual bar when there is NO space in the floor of the mouth. § INOPERABLE lingual mandibular tori that cannot be removed. § Anticipated loss of one or more of the remaining teeth. § Used in Class I designs where residual ridges have undergone excessive vertical resorption. § Used to stabilize periodontally weakened teeth (splinting) or lingually tilted mandibular incisors. § Used when future replacement of 1 or more incisors is facilitated by adding retention loops to an existing linguoplate § Used to avoid gingival irritation or food entrapment, or to cover generously relieved areas that would irritate the tongue. § Extends to the rests on the terminal abutments, to the contacts inter-proximally, and covers anterior cinguli. Do not use if there are wide open anterior contacts because it is un-esthetic or if anterior overlapping exists. § Superior border is at the middle 1/3 of the teeth’s lingual surface and extends upward to cover inter-proximal spaces to the contact point. § Mandibular lingual tori require a linguoplate because there is often not 7mm of vertical space for a lingual bar. Tissue covering the tori is thin and cannot tolerate vertical pressure from the major connector. DO NOT USE IF SEVERE ANTERIOR CROWDING EXISTS.

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OPERATIVE (RESTORATIVE) DENTISTRY CEMENTS (LUTING AGENTS) Glass Ionomer Cements (GIC)-are hybrids of silicate and polycarboxylate cements designed to combine the fluoride releasing properties of silicate particles with the chemically adhesive and more biocompatible characteristics of the polyacrylic acid matrix compared to the extremely acidic matrix of silicate cement. GICs are mixed powder-liquid component systems. The powder (calciumaluminofluorosilicate glass) reacts with a liquid (polyacrylic acid) to form a cement of glass particles surrounded by a matrix of fluoride elements. § Advantages of GIC: ! Releases fluoride (anti-cariogenic). Upon setting, GICs can inhibit recurrent caries development at its margins because it releases fluoride from its surface. GIC can also absorb fluoride when local ionic concentrations are high, then slowly release fluoride when the environment concentration decreases, thus acting as a FLUORIDE SPONGE. ! Chemical adhesion to the prepared tooth and certain materials. Micromechanical bond to composite resins. ! High biocompatibility, thus with enough dentin remaining (.5-1mm) no pulpal protective agent (calcium hydroxide) is required. ! Good thermal insulators (equal to natural dentin).Thermal expansion is similar to that of tooth structure. ! After the initial setting period, GICs have low solubility in the mouth. It is the least soluble cement (compared to zinc phosphate and zinc polycarboxylate cements). §

Disadvantage: has a higher cement film thickness than zinc phosphate cement.

§

Only GIC is used as a cement (luting agent) AND permanent restorative material. GIC are often used for root surface carious lesions (Class V restorations) due to the potential advantage of fluoride release to help control spread of caries. GIC is used as a luting agent and for Class V restorations with composite “sandwich technique”.

§

Glass ionomer cements are composed of aluminosilicate powder and polycarboxylate liquid.

CLASSES OF GLASS IONOMER CEMENTS (GIC): 1. Conventional GIC-used as a luting agent. Ex: Ketac-Cem. 2. Light-cured GIC-used as a liner or base (the liquid version has HEMA added to it). Advantages: extended working time, short on-demand setting times, as a set mass it is stronger, more adhesive, and more resistant to desiccation than self-cured glass ionomers. Ex: Vitrebond & XR Ionomer. 3. Resin-Modified (Hybrid) Light Cured GIC-used for any application where glass ionomers are good choices (the liquid has HEMA added to it). Ex: Fuji-II LC. Advantages of hybrid light cured ionomers: esthetics, bond strength, and coefficient of thermal expansion. GLASS IONOMER RESTORATIONS: both self-cured and light cured versions of GI restorations are available. Light-cured glass ionomers allow extended working time and have improved physical properties. Due to their limited strength and wear resistance, GI restorations are indicated to restore LOW STRESS AREAS where caries activity potential is a significant concern. • Are moderately esthetic, but do not polish as well as composites. • Material of choice for restoring root surface caries in patients with high caries activity. • Best surface finish for a glass ionomer restoration is obtained against a surface matrix. • Adheres to mineralized tooth tissue. • Glass ionomers have a lower compressive strength, tensile strength, and hardness than resin composites. They are very technique sensitive due to their high solubility when first mixed. 291

dentin™ | NBDE II DENTAL ADHESIVES (3 MAIN ETCH TECHNIQUES): 1. TOTAL ETCH (ETCH & RINSE)-classic technique using 30-40% phosphoric acid to prepare the enamel and dentin for the adhesive. Creates the most post-operative sensitivity as the dentinal tubules are opened by the phosphoric acid etch, and unless adequately closed by bond, the pulpirritating composition of resin irritates the pulp. Placing a glutaraldehyde-containing liquids (GLUMA) contain 5% glutaraldehyde and 35% HEMA. They coagulate dentin to obturate the tubules to reduce dentin’s permeability to the placed resin. Applying two, 1-minute applications of GLUMA, then suction off the GLUMA off (don’t wash it off or get it on soft tissue). • Advantages: prepares enamel, dentin, and sclerotic dentin for bonding yielding HIGH BOND STRENGTHS. Can be used universally as it does not interfere with polymerization of dualcured resins. •

Disadvantages: etching dentin longer than 15 seconds can yield post-operative sensitivity and decreased bond strength if the demineralization penetrates deeper into the tubules than the resin tags, thus forming a gap. To help prevent, etch the enamel first for 10 seconds then placed the etch into the prepared dentin for 15 seconds and rinse.

2. SELF-ETCH-rely on 10% maleic acid or acidic monomers to remove the smear layer and demineralize dentin and enamel. Main Advantage: LEAST POST-OPERATIVE SENSITIVITY. Disadvantage: lower bond strength than total-etch and possibly selective etch. 3. SELECTIVE-ETCH-similar to total-etch by selectively etching enamel only, rinse, place GLUMA and suction off, then place the composite. Helps reduce post-operative sensitivity. UNIVERSAL DENTAL ADHESIVES-work with all three techniques (total-etch, self-etch, and selective etch).

Generation Type

Components Smear Layer Dual Cured Activator Direct Light Cured Resin Restorations Indirect Posterior Composites Core Build-up (Self-cured Composite) Porcelain Veneers Dentin Bond Strength

ADHESIVE SYSTEM GENERATION CHARACTERISTICS 4th 5th 6th- Type I 6th-Type II Etch and Etch & Rinse Self Etch, two Self-Etch, one rinse single bottle step step application Multiple application bottle Etch, primer, adhesive Removed Yes

Etch, primer/adhesive Removed Some products

Yes

Yes with dual-cured catalyst Yes with dual/cured catalyst Yes

Yes with dualcured catalyst

17-25 MPa

20-24 MPa

Acidic primer, adhesive Modified Some products Yes

Acidic primer/adhesive Modified Some products

7th Self-Etch, combines acid, primer, and resin in single bottle (one step) Acidic primer/adhesive Modified Some Products

Yes

Yes with dual-cured catalyst Yes

Yes with dualcured catalyst

Yes with dual cured catalyst

Yes (etch or pumice enamel) 18-23 MPa

Yes (etch or pumice enamel)

18-23 MPa

18-25 MPa iBOND

Yes with dual cured catalyst Yes

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THE PERIODONTIUM & FIBERS Periodontium-tissues that surround and support the teeth consisting of the gingiva, PDL, cementum, alveolar & supporting bone. The main functions are to support, protect, and nourish the teeth. § Attachment apparatus-consists of the alveolar bone proper, PDL fibers, and cementum that attaches the root to alveolar bone. § Gingival apparatus-describes the gingival fibers and epithelial attachment. § Gingival ligament-consists of dentogingival, alveologingival, and circular fibers. § Indifferent Fiber Plexus-small collagen fibers located in the PDL that run in all directions, and are associated with the larger principal collagen fibers. Alveolar Process-the part of the maxilla and mandible that HOUSES TEETH and consists of two main parts. 1. Alveolar bone proper-the only essential part o the bone socket (alveolar process) that is always present. It is a thin inner layer of compact lamellar bone that immediately surrounds the root where PDL fibers attach. It is a perforated cribiform plate through which vessels and nerves pass between the PDL and bone marrow. It consists of two layers of bone (compact lamellar bone & layer of bundle bone (the layer that PDL fibers insert into). Alveolar bone proper helps form the attachment apparatus. 2. Supporting alveolar bone-is not always present, but surrounds the alveolar bone proper to provide SUPPORT to the socket (alveolar process) and consists of: § Cortical plate (compact lamellar bone)-forms the outer & inner plates of alveolar processes, and is thicker in the mandible than in the maxilla. §

Spongy bone (cancellated bone)-fills in the area between the cortical plates of bone. Spongy bone is NOT present in the anterior region of the mouth (here the cortical plate is fused to the cribiform plate). This is also true over the radicular buccal bone of maxillary posterior teeth.

Gingiva Components: 1. FREE GINGIVA (unattached or marginal gingiva)-the collar of tissue not attached to the tooth or alveolar bone composed of: 1. gingival margin-the most coronal part of the free gingiva. 2. free gingival groove-separates free gingiva from attached gingiva; only present in 33% of adults. 3. gingival sulcus-the shallow groove between the marginal gingiva & tooth surface, bound by sulcular epithelium laterally, and by JE apically. 4. interdental (interproximal) gingiva-occupies the interdental spaces coronal to the alveolar crest. Gingival Fibers (Supracrestal C.T. Fibers)-Type I collagen fibers that support and attach the gingiva to tooth and alveolar bone. Gingival fibers are found ONLY within the FREE GINGIVA (not in attached gingiva or mucogingival junction). Gingival fibers are continuous with the PDL (which is also C.T that surrounds the root and connects the root to alveolar bone by its principal fibers). Gingival fibers are designated by their orientation: 1. Alveologingival fibers-insert in the crest of the alveolar process and spread out through the lamina propria into the free gingiva. Also helps form the gingival ligament. 2. Circular fibers (Circumferential fibers)-resists ROTATIONAL FORCES applied to a tooth, and help form the gingival ligament. These fibers encircle the tooth around the most cervical part of the root, and insert into cementum and lamina propria of the free gingiva and alveolar crest. 353

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NERVE ANATOMY Trigeminal Nerve (CN V)-the LARGEST of the 12 cranial nerves and principal general sensory nerve to the head and face. Trigeminal exits the inferolateral pons as a sensory and motor root. The larger sensory root enters the trigeminal (semilunar, gasserian) ganglion in the middle cranial fossa. ∗ Trigeminal nerve 3 sensory divisions arise from the ganglion and leave the cranial cavity through foramina in the sphenoid bone. The smaller motor root passes under the ganglion and joins the mandibular division (V3) as it exits through FORAMEN OVALE. Mandibular division (V3) innervates 8 muscles. ∗

CN V (trigeminal) contains NO parasympathetic component at its origin.

Somatic SENSORY bodies of the ganglion’s sensory fibers enter the: 1. Ophthalmic Division (V1) supplies general sensation to the ORBIT & SKIN of the face above the eyes. 2. Maxillary Division (V2) supplies general sensation to nasal cavity, maxillary teeth, palate, & skin over the maxilla. 3. Mandibular Division (V3) supplies general sensation to the mandible, TMJ, mandibular teeth, floor of mouth, tongue, and skin of mandible. The axons of the neurons enter the PONS through the sensory root and terminate in 1 of 3 nuclei of the trigeminal sensory nuclear complex. 1. mesencephalic nucleus-mediates proprioception (i.e. muscle spindle). 2. main sensory nucleus-mediates general sensation (i.e. touch). 3. spinal nucleus-mediates pain and temperature from the head and neck. Proprioceptive fibers from muscles & TMJ are found only in trigeminal’s mandibular division (V3). Cell bodies of proprioceptive 1st order neurons are found in the mesencephalic nucleus, not the trigeminal ganglion. The TMJ (as with all joints), receives no motor innervation, however the muscles that move the TMJ receive the motor innervation. Branchiomeric motor fibers-innervate temporalis, masseter, medial & lateral pterygoids, anterior belly of digastric, mylohyoid, tensor tympani, and tensor veli palatine (palati). Mandibular Division (V3) of Trigeminal Nerve-passes through FORAMEN OVALE and supplies MOTOR innervation to tensor veli palatine, tensor tympani, muscles of mastication (temporalis, masseter, lateral & medial pterygoids), anterior belly of digastric, & mylohyoid muscles. ∗ V3 Sensory Innervation: ! Long buccal nerve (sensory only) to the cheek and mandibular buccal gingiva. ! Auriculotemporal nerve (sensory only) to TMJ, auricle, and external auditory meatus. ! Lingual nerve (sensory only) to floor of mouth, mandibular lingual gingiva, and anterior 2/3 of tongue. ! Inferior alveolar nerve (sensory & motor) to mandibular teeth, chin skin, and lower lip. Masseteric Nerve (nerve to the masseter)-branch of mandibular division (V3) that carries a few sensory fibers to the TMJ’s anterior portion. Auriculotemporal Nerve-a branch of mandibular division (V3) that provides the major SENSORY innervation to the TMJ’s posterior portion. Transmits pain in the TMJ capsule and disc periphery.

403

dentin™ | NBDE II Nerve to Mylohyoid Muscle-a branch of the mandibular nerve (V3). Mylohyoid muscle elevates the hyoid bone, base of tongue, and floor of mouth. The sublingual gland is superior to the mylohyoid muscle. ∗ When placing the film for a periapical view of mandibular molars, the mylohyoid muscle can obstruct the view if it is not relaxed. ∗

When the floor of the mouth is lowered surgically, the mylohyoid & genioglossus muscles are detached.

Anterior Triangle Muscles Muscle Nerve Innervation Suprahyoid Muscles (origin is above the hyoid bone): CN-V3 (anterior belly) CN VII (posterior belly) ∗ Digastric muscles (anterior & posterior CN-V3 bellies) C1 fibers carried via hypoglossal nerve (CN XII) ∗ Mylohyoid muscle CN VII (facial nerve) ∗ Geniohyoid muscle ∗ Stylohyoid muscle Infrahyoid Muscles (origin is below the hyoid bone): ∗ Thyrohyoid muscle All innervated by Ansa Cervicalis (a loop ∗ Omohyoid muscle formed by branches of the cervical plexus C1, ∗ Sternohyoid muscle C2, C3). ∗ Sternothyroid muscle Hypoglossal Nerve-a motor nerve supplying all intrinsic & extrinsic tongue muscles (except palatoglossus), which is supplied by the vagus nerve. It leaves the skull through the hypoglossal canal medial to the carotid canal and jugular foramen. Soon after it leaves the skull through the hypoglossal canal, it is joined by C1 fibers from the cervical plexus. It passes above the hyoid bone on the lateral surface of the hyoglossus muscle deep to the mylohyoid muscle. It loops around the occipital artery and passes between the external carotid artery and internal jugular vein. ∗

Unilateral lesions of the hypoglossal nerve cause deviation of the protruded tongue towards the affected side due to the lack of function of the genioglossus muscle on the diseased side. Injury of the hypoglossal nerve eventually produces paralysis and atrophy of the tongue on the affected side with the tongue deviated to the affected side. Dysarthria (inability to articulate) may also occur.

∗

If the genioglossus muscle is paralyzed, the tongue has a tendency to fall back and obstruct the oropharyngeal airway with risk of suffocation.

∗

Motor innervation to the tongue comes from the Hypoglossal nerve (CN XII).

CAROTID SHEATH-located at the lateral boundary of the retropharyngeal space at the level of the oropharynx on each side of the neck deep to the SCM muscle. It extends from the skull base to the first rib and sternum. It contains the carotid arteries, internal jugular vein, vagus nerve, and deep cervical lymph nodes. •

During surgical procedures of the neck, structures within the carotid sheath can be retracted (pulled aside) as a unit (common carotid artery, internal jugular vein, internal carotid artery, & vagus nerve). However, the cervical sympathetic trunk would remain in place when the carotid sheath is retracted because it is not within the sheath.

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dentin™ | NBDE II

ROOT FRACTURES Diagnostic Aids to Identify Vertical Root Fracture: 1. Fiberoptic light for transillumination. 2. Wedging the tooth in question and take an x-ray. 3. Persistent periodontal defects in an otherwise healthy tooth. 4. Have patient bite forcefully on a bite stick (tooth slooth). Root fractures are only visualized on a radiograph if the x-ray beam passes THROUGH THE FRACTURE LINE. Since the fracture line can extend diagonally, an additional radiograph is taken with a steep (45º) vertical angulation in addition to the conventional 90º degree. Inlays can cause fractures. If a patient complains of pain during mastication since inlay placement, suspect a fractured cusp (using a bite stick or tooth slooth helps determine which cusp is fractured). Vertical tooth fracture-symptoms and clinical tests show pulpal pathosis in a posterior tooth, but no decay or restoration in any proximity to the pulp on the radiograph is pathognomonic of a vertical tooth fracture. s Radiographic exam rarely reveals the fracture because the crack is usually parallel to the xray film. Radiographs (without first wedging the tooth) RARELY show vertical tooth fractures. s

Vertical fractures through root structures have an almost HOPELESS prognosis, unless the fractured segment can be removed, and gingivoplasty & alveoplasty are performed. However, unrealistic or overambitious case selection leads to failure.

s

A tooth with a vertical root fracture has a POOR prognosis. Studies show most vertical root fractures are caused by using too much condensation force during obturation with guttapercha.

Anterior tooth root fractures, usually occur in a more HORIZONTAL PLANE and may be visible on the radiograph. Anterior tooth fractures are usually due to accidental trauma (i.e. blow to the jaw/teeth). If the fracture line is not too far down the root, it may be saved with RCT and a crown. Therapy for horizontal root fractures is always difficult. Root canal treatment (RCT) is NOT indicated if the fracture site remains in close proximity and if pulp retains its vitality. However, if clinical symptoms develop, or the segments appear to be separating on the x-ray, some treatment is necessary. Cracked-Tooth Syndrome-one of the most frustrating dental conditions involving the possible need for endodontic treatment, because its symptoms are usually characterized by a SHARP, but BRIEF PAIN occurring unexpectedly only when the patient is chewing. Having a patient bite forcefully on a bite stick (tooth slooth) and noticing the cusps that occlude when the pain occurs helps locate the cracked tooth. Submarginal Curved Flap (Semilunar Flap)-a half-moon shaped flap raised with a curved horizontal incision in the mucosa or attached gingiva with the concavity towards the apex. While it is simple and does not impinge on surrounding tissue, its disadvantages outweigh its advantages, thus it is NOT used for anterior tooth root-end surgery. 1. limited access and visibility. 2. tearing of incision corners when trying to improve accessibility by stretching the flap. 3. if a lesion is larger than expected, the incision lies over the bony defect, and healing occurs by scarring. 4. incision extent is limited by attachments (i.e. frenum, muscles).

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ANTI-ANXIETY DRUGS INHALATION NITROUS OXIDE-the most frequently utilized route of administration for sedation in pediatric patients. ! Nitrous oxide is a slightly sweet smelling, colorless, inert gas that must always be coupled with at LEAST 20% oxygen. N2O is quickly absorbed from the lungs and is physically dissolved in the blood. ¶ When one turns on the N2O, the initial concentration is 20%. Initially, some start with 100% oxygen. ¶ Maximum concentration of N2O should not exceed 50% (some say 40%). ¶ When one starts conscious sedation, the flow rate is about 6 liters/minute. The correct total liter flow of nitrous oxide-oxygen is determined by the amount necessary to keep the reservoir bag 1/3-2/3 full. ¶ The earliest symptoms of conscious sedation is LIGHT HEADEDNESS. Laughing or crying, paresthesia of arms, legs, and oral cavity, and feeling of floating are seen in the second stage. ¶ After sedating a child, always keep an eye on the status of the child. ! There is no biotransformation, and the gas is rapidly excreted by the lungs when the concentration gradient is reversed. It is recommended that the patient be maintained on 100% oxygen for 3-5 minutes after the sedation period. ! N2O creates an altered state of awareness with impaired motor function. It is a CNS depressant, but produces little analgesia. The combined volume of gases being delivered (oxygen and nitrous) should be at least 3-5 liters/min. The operator should encourage the patient to breathe through their nose with the mouth closed. The feeling of floating or giddiness with tingling of the digits is the proper response to nitrous oxide. ! For restorative dentistry, N2O and local anesthesia is usually all that is needed to treat a child who fears the dentist. SEDATIVE HYPNOTICS-their principal effect is sedation and sleepiness. 1. Chloral Hydrate-a drug widely used for pediatric sedation by acting on the CNS to induce sleep. At normal doses, the sleep induction does not affect breathing, BP, or reflexes. It may be used before some surgeries or procedures to help relieve anxiety and induce sleep. When used with analgesics, it can help manage pain after surgery. Its onset of action is 15-30 min when given orally. Children often enter a period of excitement and irritability before becoming sedated. As with barbiturates, pain may cause paradoxical reactions. 2. Short-Acting Barbiturates: Secobarbital (Seconal) & Pentobarbital (Nembutal) are sedative drugs sometimes used for pediatric conscious sedation by oral administration, but are of very limited value. They are non-analgesic and may cause hyper-excitability rather than sedation in some children.

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dentin™ | NBDE II MIDAZOLAM (Versed Injection, Syrup, or Nasal Spray)-an anti-anxiety (benzodiazepine) drug that relaxes and makes child sleepy. Closely related to diazepam (Valium). •

Used in adults and children to reduce anxiety and fear. In adults, it is given through a vein in the arm. During the last 20 years, it has almost totally replaced diazepam as the drug of choice for IV sedation. It causes less burning and pain during injection. In children, it is usually given orally as a sweet-tasting syrup. Some dentists may elect to give midazolam as a nasal spray.

•

Does of IV midazolam usually is in the range of 1-5mg just before the dental procedure. Children's dosing is based on body weight, ranging from 0.25mg-0.5mg per kilogram (2.2 pounds). Maximum dose is 20 milligrams. The syrup is given to a child 30 to 45 minutes before the dental procedure.

•

Review child’s existing allergies and medications (to include OTC vitamins and herbal supplements).

•

Must monitor patient’s blood pressure, heart, pulse and breathing. Pulse oximeter to measure heart rate and indirectly, breathing. Midazolam can sometimes affect breathing. Midazolam potential side effects: nausea, vomiting, xerostomia, confusion, decreased coordination.

•

Certain drugs may cause midazolam systemic build up, thus can increase risks of Midazolam side effects. These drugs include: • Erythromycin (Eryc) and Clarithromycin (Biaxin). • Azole antifungal drugs: Ketoconazole (Nizoral) and Fluconazole (Diflucan). • Ulcer medicines: Cimetidine (Tagamet) and Omeprazole (Prilosec).

Midazolam Contraindications: • Pregnant women • Alcholics • Narrow-angle glaucoma (increased eye pressure) • Sleep apnea (can cause respiratory depression) Child Antibiotic Prophylactic Regimens for Dental Procedures Situation Antibiotic Regimen Standard general prophylaxis 50mg/kg orally 1hr before Amoxicillin procedure Unable to take oral medications Ampicillin 50mg/kg IM or IV within 30min before procedure Allergic to Penicillin 20mg/kg orally 1hr before Clindamycin procedure Cephalexin or Cephadroxil 50mg/kg orally 1hr before Azithromycin or procedure Clarithromycin 15mg/kg orally 1hr before procedure Allergic to Penicillin and cannot take oral medications

Clindamycin Cefazolin

*Remember 1.0 lb = .453kg

490

20mg/kg IV within 30min of procedure 25mg/kg IM or IV 30min of procedure

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ORTHODONTICS PRIMARY TEETH OCCLUSION: s Flush Terminal Plane-the NORMAL relationship of the primary molars in the deciduous (primary) dentition. The terminal plane relationship of primary second molars determines the future antero-posterior position of the permanent first molars. s

Mesial Step-the primary dentition’s equivalent to an Angle Class I malocclusion.

s

Distal Step-the primary dentition’s equivalent to an Angle Class II malocclusion (retruded mandible).

s

An equivalent of Angle’s Class III is almost NEVER SEEN in the primary dentition because of the normal pattern of craniofacial growth where the mandible lags behind the maxilla.

The EDGE-TO-EDGE position of permanent maxillary & mandibular first molar cusps is the MOST COMMON initial relationship (when primary molars are in a flush terminal plane). This will most likely become a Class I molar relationship by both molars drifting forward (“early mesial shift”), with the mandibular molar drifting two times farther than the maxillary molar. While erupting, the permanent teeth move OCCLUSALLY & BUCALLY. Also, during active tooth eruption, there is apposition of bone on all surfaces of the alveolar crest and on the bony socket walls. o Important: the maxillary arch is slightly longer than the mandibular arch. The sum of the M-D diameter of the maxillary permanent teeth is ~128mm, and is 126mm for the mandibular permanent teeth. OVERBITE- VERTICAL overlapping of maxillary anterior teeth over the mandibular anterior teeth. OVERJET-HORIZONTAL projection of maxillary anterior teeth beyond the mandibular anterior teeth. Labial-axial inclination of the maxillary incisors. Reverse Overjet-associated with Class III skeletal patterns with more than 2 maxillary anterior teeth in linguoversion. Physiologic occlusion-while it is not necessarily an ideal Class I occlusion, it is an occlusion that adapts to the stress of function, and can be maintained indefinitely. Physiologic tooth movement-an example is mesial drifting of a permanent molar into a space created by the premature loss of a primary molar. Important: permanent molars have a natural tendency to drift MESIALLY. Pathologic occlusion-occlusion that cannot function without contributing to its own destruction, and may manifest itself by any combination of excessive tooth wear without sufficient compensatory mechanisms, TMJ problems, pulpal changes ranging from pulpitis to necrosis, and periodontal changes. Pathologic tooth movement-tooth movement caused by pathologic conditions.

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dentinâ&#x201E;˘ | NBDE II CEPHALOMETRIC LANDMARKS: 1. Bolten (Bo)-the highest point in the upward curvature of the retrocondylar fossa of the occipital bone. 2. Baison (Ba)-the lowest point on the anterior margin of the foramen magnum, at the base of the clivus. 3. Articulare (Ar)-the intersection of 3 radiographic shadows, inferior surface of the cranial base, & posterior surfaces of the necks of the mandibular condyles. 4. Porion (Po)-the midpoint of the upper contour of the metal ear rod of the cephalometer. 5. Sphenooccipital synchondrosis (SO)-the junction between the occipital & basisphenoid bones. 6. Sella (S)-the midpoint of the cavity of the sella turcica. 7. Pterygomaxillary fissure (Ptm)-the point at the base of the fissure where the anterior & posterior walls meet. 8. Orbitale (Or)-the lowest point on the inferior margin of the orbit (floor of orbit). 9. Anterior nasal spine (ANS)-the tip of the anterior nasal spine. The point above the root the maxillary central. 10. Point A (Subspinale)-innermost point on contour of the mandible between the incisor and bony chin. 11. Point B (Supramentale)-innermost point on contour of the mandible between the incisor and bony chin. 12. Pogonion (Pog)-the most anterior point of the chinâ&#x20AC;&#x2122;s contour (on the mandibular symphysis). 13. Menton (Me)-the most inferior point on the mandibular symphysis (the bottom of the chin). 14. Gonion (Go)-the lowest, most posterior point on the angle of the mandible with the teeth in occlusion. 15. Nasion (Na)-anterior point of the intersection between the nasal and frontal bones.

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dentin™ | NBDE II

BEHAVIORAL SCIENCE Psychosocial Factors that strongly influence behavior: attitudes, beliefs, values, family, society, culture, and education. Behavior is a determined, purposeful unit of activity. • Determined-the assumption that behavior is lawful and has determinants. •

Purposeful-the assumption that behavior is goal-oriented, that is seeks to achieve positive and reduce negative need or motivational states.

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Unit of Activity-what a person does that can be reported or described as discrete elements.

Ex: teeth do not behave, individuals behave. Observing that a pulpal or periodontal problem exists is a common behavior for the dentist. Avoiding the dentist, even though an objective need exists and the patient requires treatment, is a common behavior for patients. Both meet the criterion of being determined, purposeful units of human activity. Behavioral Development-any observable response mediated through the neuromotor system. To understand the development of human behavior, you must understand the basic concepts of maturation and learning. There are 4 major fields of behavior: 1. Personal Social-is usually a function of environment, work, play, and society. 2. Motor-starting point to access maturity. 3. Language-vocalization, words, sentences, facial, and manual movements. 4. Adaptive-use of motor capacity and solutions to practical behavior. Behavior Management-the means by which the dental health team effectively & efficiently performs treatment for the patient while simultaneously instilling a positive attitude. Most researchers believe changes in behavior are a prerequisite to changes in attitude. Ex: Ashley, a 32-year-old women, comes in for her routine cleaning appointment. Stephanie, the hygienist finds that Ashley has not been following the home care program recommended six months ago. Stephanie believes Ashley’s problem is a management deficiency, not a skills deficiency. Thus, the best course of action for Stephanie to take is to meet with her supervising dentist to determine the future course of action. § Since this is not a skills deficiency problem, reviewing homecare techniques is not going to solve the problem. Ashley knows what to do. Now Stephanie and Ashley’s supervising dentist needs to find a way to motivate Ashley to find the time to brush and floss. §

The most effective way to teach oral hygiene skills is by having the patient participate in repeated, supervised training sessions.

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The best time to determine a patient’s plaque index (to assess the effectiveness of patient homecare) is at the beginning of the appointment. Rather than just asking about the patient’s homecare skills, have the patient demonstrate their brushing/flossing skills.

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Maintaining a 4-year-old child’s healthy dentition starts with educating the parent.

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Having your teeth cleaned and examined regularly and keeping them clean daily at home is the best way to prevent periodontal disease.

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Patient information required to plan dental hygiene care includes: health & dental history, dietary analysis, and periodontal examination.

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dentin™ | NBDE II Americans with Disabilities Act: both state and federal statutes define disability as having a physical or mental impairment that substantially limits one or more major life activities of the individual, a record of such impairment exists, and the patient is regarded as having such impairment. § Dentists cannot deny anyone care due to a disability and cannot dismiss employees due to a disability. §

Dental offices must undergo structural changes to allow access for the disabled.

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HIV patients are protected under the Americans with Disabilities Act.

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