NDEB AFK flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Enamel composition

Enamel is about 96% inorganic by weight, mainly hydroxyapatite, with no collagen; ameloblasts form it, and mature enamel cannot regenerate after destruction.

Dentinal tubule sensitivity

The hydrodynamic theory states that fluid movement within dentinal tubules stimulates A-delta nerve fibers, explaining sensitivity to cold, air, and osmotic stimuli when tubules are patent.

RANKL and osteoclasts

RANKL binds RANK on osteoclast precursors to promote differentiation and activation; osteoprotegerin is a soluble decoy receptor that inhibits RANKL and reduces bone resorption.

Resting membrane potential

The resting membrane potential is about -70 mV, maintained by potassium permeability and the Na/K ATPase; threshold near -55 mV opens voltage-gated sodium channels and triggers an action potential.

Trigeminal nerve branches

The trigeminal nerve divides into ophthalmic V1, maxillary V2, and mandibular V3; V3 carries motor fibers to the muscles of mastication and sensory fibers to mandibular teeth.

Salivary flow rates

Resting whole saliva flow is about 0.3–0.5 mL/min and stimulated flow about 1.5–2.0 mL/min; bicarbonate concentration and pH rise with flow, increasing acid buffering.

Periodontal ligament width

The periodontal ligament is about 0.15–0.38 mm wide and contains Sharpey fibers that attach cementum to alveolar bone and transmit occlusal forces.

Warfarin mechanism

Warfarin inhibits vitamin K epoxide reductase, reducing synthesis of functional factors II, VII, IX, and X and proteins C and S; its effect is monitored by the INR.

Pulp tissue characteristics

Dental pulp is loose connective tissue containing odontoblasts, fibroblasts, vessels, and nociceptors; because it is low-compliance, inflammation increases interstitial pressure and causes pain.

Bone remodeling coupling

Osteoblasts form bone and express RANKL, while osteoclasts resorb bone; parathyroid hormone stimulates osteoblast signaling to increase RANKL and indirectly activate osteoclasts.

Working length endpoint

Endodontic working length is typically 0.5–1.0 mm short of the radiographic apex, near the apical constriction, to limit overinstrumentation and extrusion of debris.

Ferrule effect

A ferrule is a 1.5–2 mm circumferential band of sound tooth structure above the crown margin that improves resistance to fracture and crown dislodgement.

Post space requirements

A post should leave at least 4–5 mm of apical gutta-percha seal and be approximately as long as the crown; excessive post space weakens the root.

Periodontal disease staging

Periodontitis stage uses clinical attachment loss and radiographic bone loss: stage I is under 15%, stage II 15–33%, and stages III–IV exceed 33% with complexity factors.

Caries detection ICDAS

ICDAS scores range from 0 to 6: 0 is sound, 1–2 are early enamel changes, 3–4 involve dentin, and 5–6 show cavitation; higher scores mean deeper caries.

Primary tooth eruption

Primary mandibular central incisors usually erupt at 6–10 months, and the primary dentition is complete by about 2.5–3 years with 20 teeth.

Permanent first molar eruption

Permanent first molars erupt at about 6 years, often before primary teeth are lost; they are not replacements for primary teeth and are vulnerable to early caries.

Inferior alveolar nerve block

An inferior alveolar nerve block targets the pterygomandibular space near the mandibular foramen and anesthetizes the inferior alveolar and lingual nerves; buccal soft tissue often needs a separate injection.

Antibiotic prophylaxis indication

Prophylaxis before invasive dental procedures is indicated for prosthetic heart valves, previous infective endocarditis, and certain congenital heart diseases; it is not indicated for mitral valve prolapse.

Oral cancer red flag

An oral ulcer or lesion that persists longer than two weeks, is indurated, painless, fixed, or bleeding should prompt urgent referral or biopsy to exclude malignancy.

Implant osseointegration

Osseointegration is direct structural and functional contact between bone and an implant surface without intervening fibrous tissue; stable primary stability and titanium surface roughness favor it.

Sensitivity formula

Sensitivity equals true positives divided by true positives plus false negatives; a highly sensitive test is useful for ruling out disease when the result is negative.

Specificity formula

Specificity equals true negatives divided by true negatives plus false positives; a highly specific test is useful for confirming disease when the result is positive.

Positive predictive value

Positive predictive value is true positives divided by all positive test results; unlike sensitivity, it depends on disease prevalence and falls when prevalence is low.

Incidence versus prevalence

Incidence counts new cases among people at risk per unit time; prevalence counts all existing cases at a point and increases with longer disease duration.

Relative risk

Relative risk is incidence in exposed divided by incidence in unexposed; it is used in cohort studies, and values above 1 indicate increased risk.

Odds ratio

The odds ratio is the odds of exposure among cases divided by the odds among controls; it is used in case-control studies and approximates relative risk for rare diseases.

Number needed to treat

Number needed to treat equals 1 divided by absolute risk reduction; it estimates how many patients must be treated to prevent one additional adverse outcome.

Transtheoretical model stages

The transtheoretical model stages are precontemplation, contemplation, preparation, action, and maintenance; relapse can occur and move a person to an earlier stage.

Informed consent elements

Valid informed consent requires capacity, disclosure of material risks and alternatives, comprehension, and voluntary authorization; confidentiality is a related ethical and legal duty.

Water fluoridation level

Community water fluoridation is typically maintained at about 0.7 mg/L; it reduces caries by roughly 25%, while excessive fluoride intake during enamel development can cause fluorosis.

Social determinants of health

Income, education, food security, housing, and access to care influence oral health and explain inequities more than individual behavior alone.