Which tooth has the developmental grooves shaped like a cross?()
A. The maxillary first molar
B. The mandibular first molar
C. The maxillary second molar
D. The mandibular second molar
E. The mandibular second premolar
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Which of the following descriptions about the mandibular canine is incorrect: ()
A. Its root is oblate and slender
B. There is the shallow and elongated depression on the distal surface of the root
C. The length of the distal slope of the cusp is twice as long as the length of the mesial slope
D. the angle of intersection of the mesial and the distal slopes is greater than 90 degrees
E. it can be extracted by the rotating force
During mastication, the occlusal contact occurs at the which of the teeth.()
A. buccal surface
B. lingual surface
C. mesial surface
D. distal surface
E. occlusal surface
The “six-year molars” refers to ()
A. The incisors
B. The canines
C. The premolars
D. The first molars
E. None of the above
The visible dental tissue on the longitudinal section of the crown does not include ()
A. The enamel
B. The dentin
C. The cementum
D. The pulp
E. None of the above
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