1171. Retention of amalgam restoration is obtained by :
A. Occlusal divergence
B. Occlusal convergence *
C. Straight walls
D. Resiliency of dentin
1172. In class II cavity preparation the axial depth of gingival floor should be a minimum of :
A. 0.5 mm
B. 0.8 mm *
C. 1.5 mm
D. 2.0 mm
1173. Condensation of alloys containing spherical particles require :
A. Smaller condensors
B. Rectangle condensors
C. Larger condensors *
D. Pneumatic condensors
1174. Class III amalgam restoration are usually prepared on :
A. Distal surfaces of anterior teeth
B. Mesial surfaces of canines
C. Distal surfaces of canines *
D. Distar surfaces of incisors and mesial surfaces of canines
1175. Ideally a class III amalgam restoration :
A. Does not involve the facial embrasure
B. Extends 0.2,0.3 mm into facial embrasure *
C. Extends 0.5 mm into facial embrasure
D. None of the above
1176. A retentive groove is prepared along :
A. Axiofacial line angle
B. Axiolingual line angle
C. Axiolingual line angle *
D. Incisal angle
1177. A retentive cove is prepared on :
A. Axiofaciogingival angle
B. Axiolingogingival angle
C. Axio Incisal angle *
D. Axiogingival line angle
1178. The lingual devatall has a incisogingival dimension of approximately :
A. 2.5 mm *
B. 2.0 mm
C. 1.5 mm
D. 1.2 mm
1179. The depth ofa class v cavity should be :
A. Uniform
B. Less deep gingivally *
C. Less deep incisally
D. Maximum proximally
1180. The most common cause of fracture of isthmus of a class II amalgam restoration is :
A. Delayed expansion
B. Inadequate depth of Isthmus *
C. Inadequate width of Isthmus
D. Moisture contaminations