Deck 16: Deciduous Dentition

Question 1

Decay progresses quickly in deciduous teeth due to each of the following EXCEPT one. Which one is the EXCEPTION?

A) Presence of high pulp horns
B) Thinner enamel covering crowns
C) Harder enamel
D) Thinner dentin

Answer 1

C
Enamel is deciduous teeth is not harder than that in permanent teeth. To clarify, if enamel were harder, this would make teeth more resistant to decay.

Question 2

The root of the mandibular canine is slightly shorter and more tapered than its maxillary counterpart. Both roots taper facially and apically.

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

Answer 2

B
The mandibular root is slightly shorter and more tapered than the maxillary. Both roots taper lingually and apically. Also pertinent, both roots are triangular in cross section and are almost twice as long as their crowns.

Question 3

Each of the following is true of deciduous teeth as compared with permanent teeth EXCEPT one. Which one is the EXCEPTION?

A) Deciduous teeth are generally lighter in color.
B) Dentin is thinner.
C) Pulp horns extend higher occlusally.
D) There is a pronounced cervical ridge.
E) Enamel is thicker and more protective.

Answer 3

E
The enamel is much thinner, therefore less protective, in primary teeth than in permanent. Deciduous teeth, generally lighter in color, usually appear white with a bluish cast. The dentin, which makes up the body of the tooth, is thinner in deciduous teeth. Pulp horns extend quite high occlusally, placing them much closer to the enamel than the pulp horns in permanent teeth.

Question 4

Which of these deciduous molars are wider mesiodistally than faciolingually?

A) First molars
B) Second molars
C) Maxillary molars
D) Mandibular molars

Question 5

Primary teeth are whiter than their permanent successors. They are smaller in crown dimension but have roots approximately the same size as the permanent dentition.

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

Question 6

Which deciduous root has two canals?

A) Maxillary lateral incisor
B) Maxillary second molar, mesiobuccal root
C) Mandibular canine
D) Mandibular second molar, mesial root

Question 7

The occlusal table is more narrow buccolingually because the buccal and lingual surfaces of deciduous molars taper occlusally.

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

Which of the following statements accurately describe the deciduous maxillary lateral incisor (select all that apply)?

A) The crown is smaller than a central incisor's crown.
B) The root of the lateral incisor appears much longer than its crown.
C) A common anomaly is that the maxillary lateral incisor appears peg-shaped.
D) The lateral incisor shows considerable variation in form.
E) This tooth appears similar to a deciduous central incisor.

Question 9

Although it is much smaller, the deciduous maxillary second molar resembles its permanent molar successor because the deciduous maxillary second molar has two equal-sized cusps divided by a buccal groove.

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 10

An extra margin of space is available for the eruption of the permanent canine as well as the first and second premolars because the formation of diastemas provides this extra space.

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

The root of the mandibular lateral incisor has a mesial and distal longitudinal grove running in a circular fashion. The mandibular central incisor root does not have any grooves or depressions.

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

Question 12

The teeth that erupt between 16-22 months of age are the deciduous

A) Lateral incisors
B) Canines
C) First molars
D) Second molars

Question 13

The buccocervical ridges on the deciduous molars are quite pronounced. The second molar shows the most prominence.

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

Question 14

Which deciduous molar has three or four cusps, an oblique ridge, three roots, and often has no distal pit?

A) Maxillary first
B) Maxillary second
C) Mandibular first
D) Mandibular second

Question 15

At 3 to 4 years of age, the coronal aspect of the root begins to resorb and continues apically until the tooth is shed. The process of shedding the deciduous dentition and replacement by permanent successors is called exfoliation.

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

Question 16

Which is the largest root on deciduous maxillary molars?

A) Mesiobuccal
B) Mesiolingual
C) Distobuccal
D) Lingual

Question 17

The longer and more slender deciduous roots also flare more than those of the permanent dentition because this arrangement allows room for the developing permanent tooth crowns.

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 18

Which deciduous molars have three root canals (select all that apply)?

A) Maxillary first
B) Maxillary second
C) Mandibular first
D) Mandibular second
E)Not of above

Question 19

The deciduous lateral incisors erupt prior to the central incisors. Lateral incisors erupt between 13 and 19 months whereas central incisors erupt between 16 and 22 months.

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

Question 20

Which of the following statements accurately describe the deciduous maxillary first molar (select all that apply)?

A) This tooth closely resembles the permanent maxillary second premolar.
B) This tooth is the most atypical of all maxillary molars.
C) This tooth is the most typical of all maxillary molars, closely resembling deciduous maxillary second molars.
D) Like all other maxillary molars, this tooth is wider buccolingually than mesiodistally.
E) The crown may have three or four cusps.

Question 21

Deciduous canines erupt before first molars.

Question 22

Root trunks of deciduous molars are long.

Question 23

Deciduous maxillary molars have a well-developed cusp of Carabelli.

Question 24

The crown of a deciduous maxillary first molar is much larger than that of the maxillary second molar, however the roots of the second molar are longer.

Question 25

The largest cusp on the deciduous maxillary second molar is the mesiolingual cusp.