611. How soon after a moisture contamination does a zinc containing amalgam alloy start expanding________________?
A. 24 hours
B. 1-2 days
C. 3-5 days
D. 7 days
612. The percentage of copper in high copper alloy is______________?
613. What is the working time of amalgam?
A. One to two minutes
B. Three to four minutes
C. Five to six minutes
D. Seven to eight minutes
614. Advantage of zinc containing amalgam is_______________?
A. Better handling property
B. Dimensional Stability
C. Resistance to creep
D. Toxicity to pulp and dentin
615. Discolouration of silver alloy is due to_____________?
B. Tarnish and corrosion
C. Wet corrosion
D. Dry corrosion
616. Moisture contamination of amalgam can lead to_____________?
A. Marginal breakdown
C. Delayed expansion
D. increased stresses
617. In a high copper amalgam the phase, which is eliminated is_______________?
A. Gamma 1
B. Gamma 2
C. Gamma 1 and 2
D. No phase is eliminated
618. Well premeasured capsules of amalgam can release mercury vapour during_______________?
619. In spherical alloys as compared to lathe cut____________?
A. Less condensing force is required
B. More condensing force is required
C. Both require same condensing force
D. Manipulation is easy
620. Chronic mercury toxicity results from_____________?
A. Ingestion while removing old amalgam
B. Skin contact
C. Mercury vapour
D. All of the above