Deck 12: Enamel

Question 1

What is the approximate amount of inorganic material in mature enamel?

A) 50%
B) 65%
C) 70%
D) 96%

Answer 1

96%

Question 2

After the ameloblasts are finished with both enamel appositional growth and maturation,they become part of the:

A) odontoclast population.
B) Hertwig epithelial root sheath.
C) reduced enamel epithelium.
D) cervical loop.

Answer 2

reduced enamel epithelium.

Question 3

Which of the following is a projection of the basal or secretory end of each ameloblast that faces the dentinoenamel junction?

A) Enamel spindle
B) Tomes process
C) Tomes granular layer
D) Hunter-Schreger bands

Answer 3

Tomes process

Question 4

Which of the following are partially mineralized vertical sheets of enamel matrix that extend from the dentinoenamel junction near the tooth's cervix to the outer occlusal surface?

A) Enamel tufts
B) Enamel lamellae
C) Enamel spindles
D) Enamel rods

Question 5

Which of the following can occur to mature enamel with a case of bulimia?

A) Abrasion
B) Erosion
C) Abfraction
D) Attrition

Question 6

Enamel can be lost by _____ ,which is caused by increasing the tensile and compressive forces during tooth flexure,which possibly occurs during parafunctional habits with their occlusal loading.

A) abrasion
B) erosion
C) abfraction
D) attrition

Question 7

Enamel rods interdigitate at each cusp tip to form a complex known as:

A) interrod enamel.
B) gnarled enamel.
C) perikymata.
D) imbrication lines.

Question 8

Enamel matrix is produced by the _____ cells.

A) ameloblasts
B) odontoblasts
C) odontoclasts
D) cementoblasts

Question 9

Which of the following are noted as small,dark brushes with their bases near the dentinoenamel junction within mature enamel?

A) Enamel tufts
B) Enamel lamellae
C) Enamel spindles
D) Enamel rods

Question 10

Enamel _____form the crystalline structural unit of enamel.

A) tubules
B) cuticles
C) granules
D) rods

Question 11

Which of the following cell types are not renewable during the lifetime of the tooth?

A) Ameloblasts
B) Odontoblasts
C) Odontoclasts
D) Cementoblasts

Question 12

Which of the following represent short dentinal tubules located near the dentinoenamel junction within mature enamel?

A) Enamel tufts
B) Enamel lamellae
C) Enamel spindles
D) Enamel rods

Question 13

Enamel matrix is a(n) _____ product,because ameloblasts are derived from the inner enamel epithelium of the enamel organ.

A) ectodermal
B) endodermal
C) mesodermal
D) neural crest cell

Question 14

Which of the following occurs in mature enamel due to wearing away of hard tissue as a result of tooth-to-tooth contact,especially with increased age?

A) Abrasion
B) Erosion
C) Abfraction
D) Attrition

Question 15

The crystals in the enamel rod groups bend sinusoidally to the right or left at a slightly different angle than do adjacent groups,which is shown in the:

A) Tomes granular layer.
B) Hunter-Schreger bands.
C) lines of Retzius.
D) imbrication lines of von Ebner.

Question 16

The ______ refer(s) to incremental lines that stain brown in preparations of mature enamel.

A) Tomes granular layer
B) Hunter-Schreger bands
C) lines of Retzius
D) imbrication lines of von Ebner

Question 17

Which of the following is an enamel loss that results from friction caused by excessive toothbrushing and abrasive toothpaste?

A) Abrasion
B) Erosion
C) Abfraction
D) Attrition

Question 18

In what part of the erupted tooth is mature enamel noted?

A) Anatomical crown
B) Anatomical root
C) Both anatomical crown and clinical crown
D) Both anatomical root and clinical root

Question 19

Which of the following is a pronounced incremental line in enamel?

A) Neonatal line
B) Tomes granular layer
C) Imbrication line of von Ebner
D) Enamel lamella

Question 20

Which of the following is not associated with the incremental nature of enamel?

A) Tomes granular layer
B) Lines of Retzius
C) Perikymata
D) Imbrication lines

Question 21

Which of the following occurs with the deposition of minerals into mature enamel?

A) Demineralization
B) Erosion
C) Remineralization
D) Abfraction

Question 22

Which of the following permanent teeth usually show the most attrition of enamel over time?

A) First molars
B) Second molars
C) Third molars
D) All equally show attrition

Question 23

How does mature enamel appear on a radiograph as compared to dentin or pulp of the erupted tooth?

A) Radiolucent
B) Radiopaque
C) Both dense and radiolucent
D) Both dense and radiopaque

Question 24

Which of the following can occur with an excessive amount of systemic fluoride during tooth development?

A) Enamel caries
B) Enamel dysplasia
C) Enamel erosion
D) Enamel abfraction

Question 25

Which of the following is not a usual way for erosion of enamel to occur?

A) Bulimia
B) Gastric reflux
C) Drinking carbonated drinks
D) Acid production by cariogenic bacteria