Deck 19: Dental Lamina and Enamel Organ

Question 1

The cells of the outer enamel epithelium (OEE)are indirectly responsible for enamel formation because they elongate and become ameloblasts.

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.

Answer 1

D
After elongating and changing internally,the cells of the inner enamel epithelium (IEE)become ameloblasts.This transformation makes the cells of the IEE indirectly responsible for enamel formation by ameloblasts.

Question 2

At about the sixth embryonic week,there is a continued thickening in the dental lamina.These localized thickenings correspond to the positions of the 20 teeth of the future primary dentition.

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.

Answer 2

B
The thickening of the lamina dura that forms the 20 positions for the future primary dentition begins to occur at about the eighth embryonic week.

Question 3

Skin,hair,enamel,and cementum can be adversely affected by ectodermal dysplasia because this condition causes poor development of structures arising from ectoderm.

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.

Answer 3

D
Although ectodermal dysplasia can adversely affect tissues arising from ectoderm,cementum is not affected by this condition.Cementum is formed by the dental sac,which arises from mesoderm.

Question 4

The successional lamina forms all permanent teeth EXCEPT for one type.Which type is the EXCEPTION?

A) Incisors
B) Canines
C) Premolars
D) Molars

Question 5

Each of the following statements accurately describes aspects of the development of enamel organ EXCEPT one.Which one is the EXCEPTION?

A) Buds from the dental lamina project into deeper underlying connective tissue.
B) The bud stage is the first stage in the development of enamel organ.
C) Enamel organ will eventually form enamel and cementum of teeth.
D) Cells in the middle of the buds come from outer layers of oral epithelium.
E) Cells in the periphery of the buds come from deep layers of the oral epithelium.

Question 6

Cells of the outer enamel organ (OEE)constrict and morph into ameloblasts.Stellate reticulum,in conjunction with ameloblasts,is responsible for enamel formation.

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 7

Premolars are successional because they develop from a posterior growth of the dental,or general,lamina.

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

The vestibular lamina forms in a lingual direction from the dental lamina.

Question 9

Enamel organ originates from the

A) endoderm
B) ectoderm
C) mesoderm
D) ameloblasts

Question 10

The appearance of the stratum intermedium differentiates the cap stage from the bell stage.The stratum epithelium,the fourth layer of epithelium,lies between the inner enamel epithelium and the outer enamel epithelium.

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 11

The cells between the dental papilla and the outer enamel epithelium (OEE)compose the stellate reticulum.Originating from deep layers of the oral epithelium,cells of the stellate reticulum are mesenchymal in origin.

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 12

The earliest signs of tooth development are seen during the 10th week in utero.

Question 13

The cap stage begins when the concavity of the tooth buds becomes slightly concave.

Question 14

The stratum intermedium develops during which stage?

A) Early bud
B) Late bud
C) Cap
D) Bell

Question 15

The cells of the inner enamel epithelium (IEE)are structurally similar to the cells of the outer enamel epithelium (OEE)because they both originate from the basal layer of the oral epithelium.

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 16

The outermost part of the structure of the cap stage is the outer enamel epithelium (OEE).This tissue,a continuation of the basal layer of oral epithelium,is composed of predominately pyramidal and conical-shaped cells.

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

The dental papilla is first seen in the

A) early bud stage
B) late bud stage
C) cap stage
D) bell stage

Question 18

The dental sac is composed of several layers of flat mesodermal cells that partially surround the dental papilla and enamel organ.The dental sac is another name for the dental lamina.

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 19

Without thickening of the vestibular lamina in an occlusal direction the vestibule would not exist because clefting or splitting of the epithelium would not occur.

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 20

The clefting that occurs in the thickened vestibular lamina eventually becomes a mucogingival groove.The vestibular lamina is a thickening of oral epithelium in a lingual direction.

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 21

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Successional lamina

Question 22

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Vestibular lamina

Question 23

The first stage of development of enamel organ is the cap stage.

Question 24

The dental lamina thickens first at the anterior midline.

Question 25

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Dental papilla

Question 26

The permanent molars develop from successional lamina.

Question 27

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Dental sac

Question 28

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Enamel organ

Question 29

MATCHING
An understanding of the formation of the dental lamina and enamel organ provides dental professionals with a foundation in embryology.Match each descriptive term with its appropriate anatomic formation.
a.Forms permanent incisors,canines,and premolars
b.Forms cementum
c.Forms enamel
d.Forms mucobuccal fold
e.Forerunner of primary tooth germ
f.Forms pulp
Dental lamina