1031. Fillers are added to composite resin to:

A. Increase working time.
B. Increase coefficient of thermal expansion.
C. Inhibit matrix deformation.
D. B+C. *
E. Decrease working time.

1032. Activating compound for visible light curing system:

A. Hycroquinone.
B. Ubiquinone.
C. Camphoquinone. *
D. Benzoin methyl ether.
E. Patasium oxide.

1033. In light cure system the wavelength of radiation is in excess of:

A. 100 nm.
B. 200 nm.
C. 300 nm.
D. 400 nm. *
E. 500 nm.

1034. In UV curing system, the activator employed is:

A.Benzoin methyl ether. *
B. Methylmethacrylate.
C. Hydroquinone.
D. Dibutylphthalate.
E. Benzoic acid.

1035. The stainless steel loses its resistance to corrosion if heated to a high temperature because:

A. Precipitation of chromium carbide *
B. Precipitation of carbon carbide
C. Precipitation of iron carbide
D. Precipitation of nickle carbide
E. Precipitation of cohalt carbide.

1036. What is the function of feldspar during preparation of dental porcelain of a metal ceramic Crown?

A. Feldspar forms a glass phase that is able to soften and flow slightly at porcelain firing temperature *
B. It decreases viscosity of ceramic material so that it can be applied on the metal substructure with ease
C. Feldspar due to its particle size interrupts crack propagation in the dental porcelain
D. Feldspar forms a carbon layer that flows at porcelain firing temperature
E. Feldspar helps to prevent porcelain cracking.

1037. The firing temperature of high fusing porcelain lies in the range of:

a.1600-1950oF
b.2000-3400oF
c.2350-2500°F *
d.2500 – 3400°F
e. 1000 – 1500°F

1038. Dicor is:

A. Ceramic material with unusual strength.
B. Ceramic material with excellent esthetics.
C. Ceramic material which is castable. *
D. New type of restorative resin with minimum porosity and excellent esthetics.
E. Dicor is having composite resins.

1039. Regarding Glass ionomers:

A. The powder is methyl methacrylate.
B. The powder is an aluminosilicate glass. *
C. They release mercury.
D. They are highly irritant to pulp.
E. Following initial placement they should not be protected from dehydration.

 

1040. Which of the following cements bonds to tooth structure, has an anticariogenic effect, has a degree of translucency and does not irritate the pulp?

A. Polycarboxylate cement
B. Resin cement
C. Silicate Cemenet
D. Glass ionomer cement. *
E. Zinc phosphate cement.