861. All of the following are inorganic phases used in composite resins, except?
C. lithium aluminium silicate `
D. BIS-GMA resin
E. none of the above
862. Which of the following least influences the setting time of zinc oxide-eugenol impression paste?
A. Rosin content
B. Presence of moisture
C. Change in ratio of the two pastes
D. Mixing time
E. Amount of calcium chloride
863. Silicate cement restorations should never be used?
A. adjacent to caries susceptible areas
B. in esthetically critical areas
C. in mouth breathers
D. in persons with bruxismal tendencies
864. A dental amalgam restoration (lathe cut alloy) will have higher strength if?
A. The mix is slightly overtriturated
B.highercondensation pressure is used
C. the mix is undertriturated
D. the mix has a high mercury to alloy ratio
865. The best method of avoiding air bubbles in a gypsum mold is to?
A. use vacuum investing technique
B. use a mechanical mixer
C. vibratethe mix before and after mixing
D. vibrate the invested wax pattern on a vibrator
866. Impression compound should flow easily to?
A. duplicate undercuts
B. ensure uniform cooling
C. ensure that deformation is completely elastic
D. avoid incorporation of stresses
E. record surface detail accurately
867. All of the following abrasives may he used in dentifrices, except?
A. calcium carbonate
B. sodium lauroyl sulfate
C. tricalcium phosphate
D. magnesium oxide
E. calcium pyrophosphate
868. A compound used as an activator in UV light cured resins is?
B. alkyl benzoin ether
E. tertiary amine
869. The primary advantage of microwave polymerization of resins over conventional hot waterpolymerization is that, microwave curing?
A. decreases porosity
B. is cleaner and faster
C. produces vastly superior strength and fracture resistance of resins
D. produces superior fit
870. Pyroplastic flow of porcelain is decreased by the addition of?
A. soda form of feldspar
B. boric acid
C. potash form of feldspar