451. Super abrasive is________________?

A. Sand
B. Silicon arbide
C. Diamond
D. Aluminum oxide

452. The preferred material for repair of fractured denture base is______________?

A. Chemically cure resin
B. Heat curve resin
C. Light cure resin
D. Vinyl resin

453. Dispersion of crystalline phase to strengthen ceramics results in_________________?

A. dispersed porcelain
B. Glazed porcelain
C. aluminium porcelain
D. All of the above

454. For porcelain fused to metal crown, the porcelain should have ______________?

A. High fusion expansion
B. High fusion temperature
C. Linear coefficient of thermal expansion less than that of metal
D. Linear coefficient of thermal expansion more than that of metal

455. The ideal temperature of water bath for softening fluid wax is about________________?

A. 51 to 54 degree F
B. 51 to 54 degree C
C. 70 to 75 degree F
D. 70 to 75 degree C

456. Crocus cloth is________________?

A. Emery
B. Garnet
C. Pumice
D. Rouge

457. The most toxic form of mercury is_________________?

A. Methyl and ethyl mercury
B. Mercury vapour
C. Inorganic mercury forms
D. Mercury sulphide

458. Ceramics fired to metals are processed by_______________?

A. Heat pressing
B. Machining
C. Sintering
D. Slip casting

459. When porcelain is basked against metal, it should possess a________________?

A. high fusion expansion
B. high fusion temperature
C. linear coefficient of thermal expansion less than but close to that of metal
D. Linear coefficient of thermal expansion greater than, but close to that of the metal

460. Clogging of an abrasive wheel with debris causing reduction of abrasive action is called________________?

A. Blinding
B. Buffing
C. Dressing
D. Truing