A. Facilitate venting of the mold
B. Retard the heating of the investment
C. Permit expansion of the world
D. All of the above
Related Mcqs:
- Gap between true end of casting ring and wax pattern should be______________?
A. ¼ inch
B. ½ inch
C. 3/8 inch
D. one inch - The tonsillar ring or Waldeyer’s ring consists of which of the following ________________?
A. The adenoid
B. The lingual tonsil
C. The tonsil
D. All of the above - Flux is used during casting to________________?
A. Remove the oxides formed on the gold alloy
B. Lower the melting point
C. Replace casting wax
D. Speed the burnout process - 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 - All of the following are true for traditional solution liner, except_________________?
A. It is not necessary in moderately deep cavities under glass ionomer restoration
B. Have Film thickness of 1 – 50 microns
C. Do not provide thermal or electric insulation
D. Protect the pulp from reaction products leaching out of restoration - Resistance to corrosion in a cobalt-chrome casting is due to presence of_______________?
A. High quality iron
B. Chrome
C. Cobalt
D. Nickel - Glossy smooth margins of a casting are due to_____________?
A. Shrinkage of alloy on cooling
B. Investment breakdown
C. Incomplete wax elimination
D. Incomplete gas elimination - Casting flux is used to_______________?
A. Prevent the oxidation of the metal during melting
B. increase the melting point of the flux
C. Flaring the point of the sprue attachment
D. None of the above - Function of wetting agents used in casting procedure is_________________?
A. To felicitate wetting of ring liner
B. To felicitate mixing investment
C. To reduce contact angle of liquid with max surface
D. For better wax elimination - Which zone is the hottest and efficient burning zone of the flame used for casting ?
A. Oxidizing zone
B. Reducing zone
C. Combustion zone
D. None of the above
