1161. Which of the following is not true about lubricant for rubber dam placement :

A. Should have a water miscible vehicle
B. Vaseline is an ideal choice *
C. Should be easy to remove
D. Should not interfere with bonding procedure

1162. A major factor determining the efficiency of bur is :

A. Taper angle
B. Spiral angle *
C. Head lenght
D. Head diameter

1163. The most important design characteristic ofa bar blade is :

A. Rake angle *
B. Edge angle
C. Clearance angle
D. Taper angle

1164. Diamonds are superior to burs for cutting :

A. Cementurn
B. Dentin
C. Enamel *
D. Soft tissue

1165. Protective measures are required when the noise level reaches :

A. 75-85 DB *
B. 40-60 DB
C. 100-110 DB
D. Above 110 DB

1166. The threshold limit value for mercury exposure is :

A. 0.01 MG/M3
B. 0.05 mg/m3 *
C. 0.1 mg/m3
D. 0.01 mg/m3

1167. The number 14 in formulate 14:4:5 indicates that the blade is :

A. 0.14 mm in width
B. 1.4 mm in width *
C. 14 mm in width
D. 14 blade angle

1168. Enameloplasty is indicated when the depth of fissure is :

A. 1/2 the thickness of enamel
B. 2/3 the thickness of enamel
C. 1/4-1/3 the thickness of enamel *
D. None of the above

1169. The amalgam restoration :

A. Covers the area of enameloplasty
B. Does not cover the area of enameloplasty *
C. Extends partly into the area of enameloplasty
D. Extends beyond the area of enameloplasty

1170. The cavosurface angle for a amalgam cavity should be :

A. 45
B. 30
C. 90 *
d. 15