761. The mercury content of the finished amalgam restoration should be approximately
A. 40%
B. 50%
C. 60%
D. less than 35%

762. The lost wax technique was first described in
A. 1907 by Taggart
B. 1930 by Skinner
C. 1898 by Hollenback
D. 1765 by jelenko

763. Which of the following properties would be of least importance, when selecting an impressionmaterial?
A. Dimensional stability
B. Biocompatibility
C. Flow
D. Adhesion
E. Ease of manipulation

764. The polymer: monomer ratio for heat-cured acrylic resinFCPS Part 1 Dentistry
A. is about 1 to 3 by volume
B. if too high will result in granularity of the acrylic
C. if too high will result in excessive shrinkage
D. if too high will have a longer reaction time

765. Which portion of the set silicate resto-ration disintegrates first in oral fluids?
A. Calcium fluoride flux
B. Gel matrix
C. Silicon dioxide particles
D.Zn3(PO4)2 buffer
E. All portions disintegrate together

766. Copper and silver in dental amalgam
A. increase compressive strength and expansion
B. aid in amalgamation and decrease expansion
C. reduce hardness and expansion only
D. decrease hardness, flow, expansion and compressive strength

767. When epoxy resins are used for die fabrication, the resultant die will
A. be slightly undersize
B. not burn out in the furnace
C. have poor abrasion resistance
D. have low strength
E. all of the above

768. Which of the following cannot result in surface roughness or irregularities of gold castings?
A. Under heating the mold
B. Heating the alloy to too high a temperature
C. Employing too high casting pressures
D. Prolonged heating of the mold
E. None of the above

769. Silicate cement powders are made up of oxides or fluorides of all of the following, exceptFCPS Part 1 Dentistry
A.aluminium
B. tin
C. calcium
D. sodium
5.silicon

770. Sodium N-lauroylsarcosinate is used in dentifricepastes as a
A. detergent
B. humectant
C. therapeutic agent
D. Binder