631. The term given to the phenomenon of moisture absorption by an alginate impression in________________?
A. Imbibition
B. Hysteresis
C. Syneresis
D. Gelation
632. The impression with the least dimensional change upon disinfection is_______________?
A. Addition poly silicone
B. Polysulphide
C. Agar-agar
D. Polyether
633. Palladium is added to polyvinyl siloxane to_____________?
A. Act as a scavenger
B. Acts as plasticizer
C. Helps as surfactant
D. Acts as a catalyst
634. Immediate pouring of impressions is most critical in_____________?
A. Condensation polysillicon
B. Polyether
C. Addition Polysilicon
D. A and B
635. The impression material used to record the prepared areas on abutment teeth is______________?
A. Medium viscosity elastomeric impression material
B. High viscosity elastomeric impression material
C. Low viscosity elastomeric impression material
D. None of the above
636. Alginate impression material is________________?
A. Thermoplastic impression material
B. Non-elastic impression material
C. More mucostatic than ZOE
D. Less mucostatic than ZOE
637. Syringe material is______________?
A. Medium viscosity elastomer
B. High viscosity elastomer
C. Medium & low viscosity elastomer
D. Low viscosity elastomer
638. The impression for a diagnostic cast of a partial edentulous mouth should be taken in_______________?
A. Modelling compound
B. Impression wax
C. Hydro-colloid
D. Hydro cal
639. Agar impression materials differ from alginate impression materials in that the former sets by_______________?
A. Evolution
B. Physical change
C. Mechanical action of saliva
D. Chemical change
640. Which material undergoes hysteresis ?
A. Impression plaster
B. Reversible hydrocolloid
C. Irreversible hydrocolloid
D. Metallic oxide paste