A. Eugenol
B. Calcium Hydroxide
C. Zinc oxide
D. Silica
✅ The correct answer is option B. Calcium Hydroxide.
Dental Materials
Condensation shrinkage of porcelain during firing depends on__________________?
A. Rate of arriving at firing temperature
B. Uniformity of particle size
C. Shape and size of particle
D. Type of investment used
✅ The correct answer is option C. Shape and size of particle.
The percentage of copper in high copper alloy is______________?
A. 10-12%
B. 0-6%
C. 13-30%
D. 20-30%
✅ The correct answer is option C. 13-30%.
The temperature (in °F) of the mixing slab for silicate cements should be_____________?
A. 55 – 65
B. 65 – 75
C. 75 – 85
D. 85 – 95
✅ The correct answer is option B. 65 – 75.
Porosity in porcelain can be prevented by_______________?
A. Thoroughness of condensation
B. Rapidity of firing
C. High firing temperature
D. All of the above
✅ The correct answer is option A. Thoroughness of condensation.
Chronic mercury toxicity results from_____________?
A. Ingestion while removing old amalgam
B. Skin contact
C. Mercury vapour
D. All of the above
✅ The correct answer is option D. All of the above.
In non-eugenol pastes the constituents are mixed in______________?
A. Phosphoric Acid
B. Ethyl alcohol
C. Benzoic acid
D. None of the above
✅ The correct answer is option C. Benzoic acid.
High copper dental amalgams are superior to other amalgams because high copper dental amalgems______________?
A. Have less marginal breakdown
B. Are workable at lower Hg-alloy ratio
C. Have a higher ratio of tensile to compressive strength
D. Have less resistance to tarnish and corrosion
✅ The correct answer is option A. Have less marginal breakdown.
Which phase provides maximum strength in hardened mercury/silver alloy ?
A. Silver / Mercury phase
B. Silver / Tin phase
C. Tin / Mercury phase
D. Zinc / Mercury phase
✅ The correct answer is option B. Silver / Tin phase.