351. Elastomers except: Polyether are_______________?

A. Hydrophilic
B. Hydrophobic
C. Water loving impression materials
D. Potassium alginates

352. Hardening solutions are used with impression made of________________?

A. Hydrocolloid
B. Impression compound
C. Elastomer
D. Zinc oxide eugenol

353. Alginate impression material is similar to Agar-agar impression material in the following respect________________?

A. Gelation increase in both on increase in temperature
B. Mixing time is increased to reduce the setting time
C. Deformation during removal of impression occurs due to distortion of gel fibers
D. Both can be re-used for fresh impressions

354. Gelation temparature of agar is between________________?

A. 20°C to 25°C
B. 27°C to 33°C
C. 37°C to 50°C
D. 55°C to 60°C

355. Brush heap structure is found in______________?

A. Zinc oxide impression material
B. Agar
C. Condensation silicone
D. Polyether

356. Masterial causing minimum tissue distortion is______________?

A. Polysulphide
B. Silicone
C. Impression plaster
D. Zinc oxide eugenol paster

357. Inelastic impression material is_____________?

A. Impression compound
B. Alginate
C. Agar-agar
D. Polyether

358. One of the most important advantages of truly elastic impression material would be its capacity for______________?

A. Close adaptation to soft tissues
B. With drawl without permanent distortion
C. Reproduction of surface details
D. Compatibility with gypsum products

359. Impression compound base_____________?

A. Low thermal conductivity
B. Crystalline structure
C. Formation of cross linkage with heating
D. High fusion temperature

360. Hypersensitivity reactions like contact dermatitis can be caused by______________?

A. polysulfides
B. Condensation silicones
C. addition silicones
D. Polyether