231. The sprue in wax pattern should be placed________________?

A. At right angle
B. At 45°C angle
C. At obtuse angle
D. It depend upon type of wax pattern

232. Gold content of an 18 carat alloy is______________?

A. 25%
B. 50%
C. 75%
D. 100%

233. Titanium casting is done_____________?

A. Under vacuum in argon atmosphere
B. Under air pressure in nitrogen atmosphere
C. In specially fabricated aluminium vanadium
D. Using CAD-CAM technique

234. Heat hardening is the process done at_______________?

A. Heating 750°C and slowly cooling to zero degree
B. Heating quickly upto 450°C followed by sudden quenching
C. Heating upto 250°C for 15 to 30 min
D. Heating at 750°C and then quenching to room temperature

235. Crucible indicated for casting base metal alloys is______________?

A. Carbon crucible
B. Clay crucible
C. Quartz crucible
D. High melting plastic crucible

236. Which of the following refractory is used to counteract most of the expansion________________?

A. Quartz
B. Cristobalite
C. Tridymite
D. Corundum

237. Passivating alloys are_______________?

A. Cr, Al, Ti
B. Cr, Mo, Ti
C. Cr, Gold, Ti
D. Cr, Fe, Ti

238. Waxes are used for_______________?

A. Primary impression
B. Corrective impressions
C. Impression of single tooth
D. None of the above

239. A common electrolyte used for plating copper indirect dies is_______________?

A. Copper cynide
B. Ionic copper
C. Acidic copper sulfate
D. Silver cyanide

240. Stainless steel is used mostly in dentistry_________________?

A. To strength amalgam
B. In orthodontic wires
C. To construct clasps for partial dentures
D. To replace internal gold restorations

NOTE
IF YOU THINK ANY OF THE MCQ ABOVE IS WRONG.
PLEASE COMMENT WITH CORRECT ANSWER AND ITS DETAIL EXPLANATION IN COMMENT BOX.
THANK YOU

Leave a Reply