1011. A greater amount of cross-linking agent is used in resin teeth, in order to?
A. reduce their tendency to crazing
B. facilitate their bonding to the denture base
C. increase their flexibility
D. all of the above
E. none of the above

1012. The knoop hardness number of which one of the following materials is closest to that of dentin (KHN 65)?

A. Tooth enamel.
B. Amalgam.
C. Pure Gold.
D. Silicate cement. *
E. Dentine.

1013. KHN of enamel is:

A. 90-100.
B. 100.50.
C. 300.
D. 600. *
E. 60-90.

1014. Which of the following impression materials is elastic?

A. Impression compound.
B. Zinc oxide – Eugenol paste.
C. Wax.
D. Polyether rubber base. *
E. Low fusing compound

1015. Which one of the following is the safest and most reliable method of regulating setting time of gypsum products?

A. Altering the water and powder ratio.
B. Controlling the temperature of water to be used for mixing. *
C. Speed of hand spatulation.
D. Length of hand spatulation.
E. Adding salt in mixing.

 

1016. Which of the following impression materials can be electroplated without risk of distortion?

A. Polysulphide. *
B. Condensation silicone.
C. Addition silicone.
D. Hydrocolloid impressions .
E. Polyether.

1017. Which of the following statements relates best regarding cavity varnish?

A. Varnishes are synthetic resins dissolved in acetone . *
B. Varnishes are calcium hydroxide in a resin base.
C. Varnishes are used to insulate the pulp thermally.
D. Varnishes are used beneath restorative resins to insulate the
pulp against chemical irritants.
E. Varnishes are base of ZnO engenol.

1018. Setting expansion of casting investment is approximately:

A. 0.1-0.2%.
B. 0.1-0.5%. *
C. 0.8-1%.
D. 1.1-1.7%.
E. 1.7%-2%.

1019. Stiffness refers to

A. Resistance to elastic deformation. *
B. Degree of elastic deformation.
C. Expandability on heating.
D. Shrinkage on cooling.
E. Expansion on cooling.

1020. What is trituration

A. Surface discoloration of metal.
B. Mixing of amalgam alloy with mercury. *
C. Same as erosion.
D. Same as corrosion.
E. Mixing of allow particles.