Deck 7: Dental Anomalies

Question 1

A dilacerated root is one that exhibits

A) bifurcated roots
B) twisted roots
C) a sharp bend in the root
D) short,fused roots

Answer 1

C
A dilacerated root is one that exhibits a sharp bend or curve of more than 40 degrees in the root.Although curved roots commonly occur,the term dilaceration is reserved for teeth with very sharp bends.Dilaceration can also occur in the crown.Another term,flexion,is often used to describe a sharp curvature or twist of a tooth root only.

Question 2

Which permanent tooth is the LEAST likely to be congenitally missing?

A) Maxillary lateral incisor
B) Mandibular second premolar
C) Maxillary third molar
D) Mandibular third molar

Answer 2

B
Of the listed teeth the mandibular second premolar is the least likely to be congenitally missing.The most commonly missing permanent teeth are third molars,with maxillary absent more than mandibular.The second most likely are the permanent maxillary lateral incisors.

Question 3

Each of the following is an example of microdontia EXCEPT one.Which one is the EXCEPTION?

A) Mesiodens
B) Paramolar
C) Distomolar
D) Tubercle
E) Enamel pearl

Answer 3

E
Enamel pearls are small masses of excess enamel on the surface of teeth located apically to the cementoenamel junction (CEJ).Enamel pearls are formed by a small,misplaced group of ameloblasts.The remaining selections are all variations of microdontia,which is an anomaly associated with teeth that are too small.

Question 4

The canines are LEAST likely of all permanent teeth to be congenitally missing because unlike other permanent teeth,canines begin to calcify by about the fourth of fifth month of fetal life.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 5

An unusually large tooth is an example of

A) hyperdontia
B) fusion
C) gemination
D) macrodontia

Question 6

Enamel dysplasia is associated with each of the following EXCEPT one.Which one is the EXCEPTION?

A) Fluorosis
B) Amelogenesis imperfecta
C) Turner's tooth
D) Enamel hypocalcification
E) Dilaceration

Question 7

Fusion involves the joining of two adjacent teeth at the cementum because this process is associated with excessive production of cementum.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 8

A distomolar is attached to the distal surface of a maxillary molar.Maxillary distomolars are the most common supernumerary teeth.

A) Both statements are true.
B) The first statement is true,the second statement is false.
C) The first statement is false,the second statement is true.
D) Both statements are false.

Question 9

Gemination occurs most frequently in the permanent dentition.It is the splitting of the tooth into two crowns and separate roots.

A) Both statements are true.
B) The first statement is true;the second statement is false.
C) The first statement is false;the second statement is true.
D) Both statements are false.

Question 10

Supernumerary maxillary teeth are more common than supernumerary mandibular teeth because metabolic intrinsic factors within the palate produce more hyperdontia.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 11

An odontoma is composed of each of the following EXCEPT one.Which one is the EXCEPTION?

A) Dentin
B) Pulp
C) Enamel
D) Cementum

Question 12

The MOST commonly missing permanent teeth are the maxillary premolars.The next teeth MOST likely to be missing are the permanent maxillary lateral incisors.

A) Both statements are true.
B) The first statement is true,the second statement is false.
C) The first statement is false,the second statement is true.
D) Both statements are false.

Question 13

Each of the following is true of dentinogenesis imperfecta EXCEPT one.Which one is the EXCEPTION?

A) The pulp is filled with dentin.
B) The tooth appears translucent.
C) Enamel cannot develop over defective dentin.
D) It is a hereditary developmental anomaly.
E) All of the above are true.

Question 14

Dens in dente,or dwarfed roots,is a developmental variation that occurs because the outer surface of the tooth crown invaginates by turning itself inward prior to mineralization.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 15

A fourth molar may be described by each of the following EXCEPT one.Which one is the EXCEPTION?

A) Macrodont
B) Distomolar
C) Supernumerary tooth
D) Supplemental tooth
E) Hyperdont

Question 16

Fusion of roots of adjacent teeth at the cementum is called concrescence and is primarily caused by dilaceration.Gemination is the deposition of excessive secondary cementum.

A) Both statements are true.
B) The first statement is true,the second statement is false.
C) The first statement is false,the second statement is true.
D) Both statements are false.

Question 17

An anomaly common to mandibular second premolars is

A) dwarfed roots
B) buccal tubercles
C) accessory roots
D) large lingual cusps

Question 18

Turner's tooth results in notched incisors and mulberry molars because prenatal syphilis disturbs normal tooth formative processes.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 19

Intrinsic factors that can contribute to dental anomalies include all of the following EXCEPT

A) mutations
B) heredity
C) metabolic dysfunction
D) nutritional deficiencies

Question 20

Tetracycline staining is an enamel dysplasia that occurs because an expectant mother or young child with tooth crowns still developing takes the antibiotic tetracycline.

A) Both the statement and the reason are correct and related.
B) Both the statement and the reason are correct but are NOT related.
C) The statement is correct,but the reason is NOT correct.
D) The statement is NOT correct,but the reason is correct.
E) NEITHER the statement NOR the reason is correct.

Question 21

Anomalies are caused by intrinsic factors only.

Question 22

A child who has congenitally missing maxillary canines will have congenitally missing permanent canines.

Question 23

A patient who has had four teeth extracted for orthodontia has true partial anodontia.