NBDE Part I UPDATED ACTUAL Exam
Questions and CORRECT Answers
Dilaceration - CORRECT ANSWER - A severe angulation or curve in the root AND
crown of a tooth that is thought to result from trauma during development
Hutchinson's Incisors (Syphilitic Hypoplasia) - CORRECT ANSWER - When an incisor is
congenitally missing the middle lobe due to a prenatal syphilis infection.
Mulberry Molars (Syphilitic Hypoplasia) - CORRECT ANSWER - Constriction of the
occlusal table and disorganized surface anatomy due to syphilitic infection during development.
Turner's Tooth (Turner's Hypoplasia) - CORRECT ANSWER - Where a permanent tooth
erupts into the mouth with a hypocalcification spot due to insult from an abscessed or
traumatized primary tooth.
Since it's hypo calcification, that means it is in a higher caries risk.
Anodontia/hypodontia/
oligiodontia/hyperdontia; basically anything with
-dontia is - CORRECT ANSWER - a GENETIC etiology during the LAMINA stage
Hyperdontia - CORRECT ANSWER - Extra (supernumerary) teeth.
Hypodontia - CORRECT ANSWER - Too few teeth. Most commonly 3rd molars, 2nd
premolars and Mx laterals.
(Total) Anodontia - CORRECT ANSWER - all teeth congenitally missing. Has a genetic
etiology.
,Partial Anodontia - CORRECT ANSWER - One or a few missing teeth
Result of hereditary factors that preclude the initiation of the tooth buds
Most commonly missing teeth: 3rd molars, maxillary lateral incisors, mandibular 2nd premolars
Least common missing teeth: canines
Oligiodontia - CORRECT ANSWER - 6 or more congenitally missing teeth, excluding the
3rd molars
abnormal tooth size - CORRECT ANSWER - Caused by a distance during the bell stage of
morphodifferentiation
Most commonly has a genetic etiology (all with
-dontia, has genetic etiology)
True Macrodontia - CORRECT ANSWER - ALL teeth are enlarged
False Macrodontia - CORRECT ANSWER - 1 or a few teeth too large
Most commonly seen in canines, incisors, and mandibular 3rd molars
True Microdontia - CORRECT ANSWER - ALL teeth are abnormally small. Rare
disorder. Seen in cases of growth hormone deficient dwarfism.
False Microdontia - CORRECT ANSWER - ♣ Most common tooth size abnormality
♣ Individual teeth appearing smaller than normal
♣ Most commonly affects maxillary lateral incisors (Peg lateral) and maxillary 3rd molars
, Microdontia - CORRECT ANSWER - Teeth too small. Most commonly a peg lateral
incisor. False Microdontia - Most affects permanent maxillary laterals (peg laterals).
Dental Fluorosis - CORRECT ANSWER - Mottled enamel
Hypomaturation of the enamel due to excess ingestion of fluoride during enamel formation.
Forms caries resistant teeth.
Attrition - CORRECT ANSWER - Wearing away of tooth structure by grinding or
clenching. Causes loss of vertical dimension.
Abrasion - CORRECT ANSWER - Wearing away of tooth structure by an object.
(toothbrush, floss, bobby pins)
Tooth Erosion - CORRECT ANSWER - Wearing away of tooth structure by chemical
dissolution. (Dietary acid or gastric acid)
Abfraction - CORRECT ANSWER - Wearing away of tooth structure near the CEJ by
flexural forces exerted during heavy occlusion. Resembles toothbrush abrasion.
Impaction - CORRECT ANSWER - Teeth fail to erupt.
Ankylosis - CORRECT ANSWER - Where bone fuses to the cementum and dentin of a
tooth. Prevents exfoliation of primary teeth and eruption of underlying permanent tooth.
Supernumerary teeth - CORRECT ANSWER - an excessive number of teeth that has a
normal morphology
Questions and CORRECT Answers
Dilaceration - CORRECT ANSWER - A severe angulation or curve in the root AND
crown of a tooth that is thought to result from trauma during development
Hutchinson's Incisors (Syphilitic Hypoplasia) - CORRECT ANSWER - When an incisor is
congenitally missing the middle lobe due to a prenatal syphilis infection.
Mulberry Molars (Syphilitic Hypoplasia) - CORRECT ANSWER - Constriction of the
occlusal table and disorganized surface anatomy due to syphilitic infection during development.
Turner's Tooth (Turner's Hypoplasia) - CORRECT ANSWER - Where a permanent tooth
erupts into the mouth with a hypocalcification spot due to insult from an abscessed or
traumatized primary tooth.
Since it's hypo calcification, that means it is in a higher caries risk.
Anodontia/hypodontia/
oligiodontia/hyperdontia; basically anything with
-dontia is - CORRECT ANSWER - a GENETIC etiology during the LAMINA stage
Hyperdontia - CORRECT ANSWER - Extra (supernumerary) teeth.
Hypodontia - CORRECT ANSWER - Too few teeth. Most commonly 3rd molars, 2nd
premolars and Mx laterals.
(Total) Anodontia - CORRECT ANSWER - all teeth congenitally missing. Has a genetic
etiology.
,Partial Anodontia - CORRECT ANSWER - One or a few missing teeth
Result of hereditary factors that preclude the initiation of the tooth buds
Most commonly missing teeth: 3rd molars, maxillary lateral incisors, mandibular 2nd premolars
Least common missing teeth: canines
Oligiodontia - CORRECT ANSWER - 6 or more congenitally missing teeth, excluding the
3rd molars
abnormal tooth size - CORRECT ANSWER - Caused by a distance during the bell stage of
morphodifferentiation
Most commonly has a genetic etiology (all with
-dontia, has genetic etiology)
True Macrodontia - CORRECT ANSWER - ALL teeth are enlarged
False Macrodontia - CORRECT ANSWER - 1 or a few teeth too large
Most commonly seen in canines, incisors, and mandibular 3rd molars
True Microdontia - CORRECT ANSWER - ALL teeth are abnormally small. Rare
disorder. Seen in cases of growth hormone deficient dwarfism.
False Microdontia - CORRECT ANSWER - ♣ Most common tooth size abnormality
♣ Individual teeth appearing smaller than normal
♣ Most commonly affects maxillary lateral incisors (Peg lateral) and maxillary 3rd molars
, Microdontia - CORRECT ANSWER - Teeth too small. Most commonly a peg lateral
incisor. False Microdontia - Most affects permanent maxillary laterals (peg laterals).
Dental Fluorosis - CORRECT ANSWER - Mottled enamel
Hypomaturation of the enamel due to excess ingestion of fluoride during enamel formation.
Forms caries resistant teeth.
Attrition - CORRECT ANSWER - Wearing away of tooth structure by grinding or
clenching. Causes loss of vertical dimension.
Abrasion - CORRECT ANSWER - Wearing away of tooth structure by an object.
(toothbrush, floss, bobby pins)
Tooth Erosion - CORRECT ANSWER - Wearing away of tooth structure by chemical
dissolution. (Dietary acid or gastric acid)
Abfraction - CORRECT ANSWER - Wearing away of tooth structure near the CEJ by
flexural forces exerted during heavy occlusion. Resembles toothbrush abrasion.
Impaction - CORRECT ANSWER - Teeth fail to erupt.
Ankylosis - CORRECT ANSWER - Where bone fuses to the cementum and dentin of a
tooth. Prevents exfoliation of primary teeth and eruption of underlying permanent tooth.
Supernumerary teeth - CORRECT ANSWER - an excessive number of teeth that has a
normal morphology
