A. Shrinkage of alloy on cooling
B. Investment breakdown
C. Incomplete wax elimination
D. Incomplete gas elimination
Related Mcqs:
- Resistance to corrosion in a cobalt-chrome casting is due to presence of_______________?
A. High quality iron
B. Chrome
C. Cobalt
D. Nickel - Fins and spines on the casting is seen due to_______________?
A. Prolonged heating:
B. Rapid heating me
C. Water film contamination
D. Too high pressure during casting - Air bubbles formed on the surface of casting is probably due to________________?
A. Improper casting pressure
B. Improper heating of the investment
C. Improper angulation of sprue
D. Improper wetting of the wax pattern by the investment - The restoration which shows percolation and shrinkage along the margins is_____________?
A. Composites
B. Unfilled resins
C. Amalgam
D. Polycarboxylate - Addition of large amounts of platinum to a casting gold alloy will________________?
A. Decrease its strength and ability to be hardened
B. Decrease its tarnish resistance
C. Increase its fusion temperature
D. Redden the alloy - Crucible indicated for casting base metal alloys is______________?
A. Carbon crucible
B. Clay crucible
C. Quartz crucible
D. High melting plastic crucible - Titanium casting is done_____________?
A. Under vacuum in argon atmosphere
B. Under air pressure in nitrogen atmosphere
C. In specially fabricated aluminium vanadium
D. Using CAD-CAM technique - Asbestos liner is used in a casting ring to________________?
A. Facilitate venting of the mold
B. Retard the heating of the investment
C. Permit expansion of the world
D. All of the above - Impurities in casting is removed by________________?
A. Annealing
B. Degassing
C. Pickling
D. Conditioning - The gold alloys used for casting contain at least…. percent of precious metal according to ADA specification number 5________________?
A. 55
B. 65
C. 75
D. 85
