A. Proximal surface of tooth
B. Cervicl region of tooth
C. Cusp tips of tooth
D. All of the above
# The key hole pattern appearance in the cross section is a feature of :
A. Aprismatic enamel
B. Prismatic enamel
C. Intertubular dentin
D. Intratubular dentin
# Neonatal lines are seen in :
A. Enamel of deciduous incisors
B. Enamel of permanent incisors
C. Enamel of premolars
D. Dentin of all teeth as it is formed first
# The shallow furrows on the enamel surface where Striae of Retzius end are known as:
A. Cracks
B. Pellicle
C. Perikymata
D. Enamel lamellae
# Maximum amount of phosphate is seen in:
A. Bone
B. Enamel
C. Gingiva
D. Dentin
# Dark bands that are present in enamel rods at intervals of 4 micrometers are:
A. Neonatal Bands
B. Cross striations
C. Striae of Retzius
D. Hunter Schreger bands
# Which of the following is correct about enamel crystals?
A. Same as dentin crystals
B. Contains organic portion in the center
C. Roughly hexagonal in shape
D. Their diameter is about 5 microns in size
# Water content in enamel by volume is :
A. 2-3 %
B. 6-7 %
C. 20- 25 %
D. 10-12 %
# Non acidic, non ionic protein which helps in enamel mineralization:
A. Tuftelin
B. Sheathlin
C. Enamelin
D. Amelogenin
# Enamel can act in a sense like a :
A. Permeable membrane
B. Impermeable membrane
C. Semipermeable membrane
D. Infrapermeable membrane