21

110. Ameloblast differentiation starts at the
 

a. incisal region of the tooth germ
b. cervical region of the tooth germ
c. junction of IDE and ODE (cervical loop)
d. lateral regions of the tooth germ
e. junction of stratum intermedium and stellate reticulum

 
111. Which one of the following dental (enamel) organs is usually the first to develop?
 

a. lst permanent molar
b. 2nd deciduous molar
c. permanent central incisor
d. deciduous central incisor
e. deciduous canine

 
112. Most principal fibers of the periodontal ligament insert into
 

a. attached gingiva
b. bone
c. dentin
d. free gingiva
e. cementum

 
113. Collagen fibers produced by cementoblasts generally lie in the matrix of cementum
 

a. parallel to Sharpey's fibers
b. parallel to the surface of the cementum
c. perpendicular to the dentino-cemental junction
d. randomly
e. either b or d

114. The gingival area where nonkeratinized epithelium most frequently occurs and which,

therefore, may be considered most vulnerable to inflammation is the

a. sulcular surface of the free gingiva
b. palatal gingiva
c. unattached gingiva
d. buccal gingiva
e. attached gingiva

115. Enamel undergoes a marked physical and chemical transition during the
 

a. desmolytic stage
b. morphogenic stage
c. maturation stage
d. secretory stage
e. protective stage