Asbestos liner is used in a casting ring to________________?

Related Mcqs:

1. 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

2. 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

3. 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

4. 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

5. 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

6. Resistance to corrosion in a cobalt-chrome casting is due to presence of_______________?

   A. High quality iron
   B. Chrome
   C. Cobalt
   D. Nickel

7. 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

8. 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

9. 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

10. 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