961. Gypsum bonded investments contain?
A. alpha-hemihydrate
D.none of the above

962. The boiling point of pure methyl meth-acrylate is?

963. Compared to the unfilled restorative resins cured by the benzoyl peroxide-tertiary amine system, those cured by the sulfinic acid system?
A. are more sensitive to inhibition by phinolic compounds
B.deteriorate more rapidly on storage
C.are less affected by water or moisture during polymerization
D.all of the above
E.none of the above

964. What is the primary objective of trituration?
A. Pushing the mercury in to the alloy particles mechanically
B.Breaking the alloy particles into smaller fragments
C.Removal of impurities from the surface of the mercury particles
D.Removal of the oxide film of the alloy particles

965. The binder in porcelain is?
A. soda form of feldspar

966. Which of the following is an advantage of the fluid resin technique of processing dentures?
A. Improved bonding of resin to teeth
B.Teeth do not shift
C.Better tissue fit
D.Avoidance of air inclusion porosities

967. Themost commonly used initiator in denture base resins is?
A. benzene
C.benzoyl peroxide
D.methyl peroxide

968. The best method of regulating the setting time of gypsum products is by varying the?
A. concentration of modifying chemicals
B.temperature of mixing water
C.W/P ratio
D.time of spatulation
E.speed of spatulation

969. The mercury used for dental amalgam alloys should?
A. not contain more than 1.5% arsenic
B.contain less than 0.2 % non-volatile residue
C.be triple distilled
D.contain less than 1.5% volatile residue

970. Which of the following may be used as a filler in composite resins ?
A.Crystalline quartz
B.Lanthanum glass
C. Beta-eucryptite
D. Lithium glass ceramics
E. All of the above

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