1. Following is added to zinc polycarboxylate to improve its manageability: Aluminium oxide Stannous fluoride Magnesium oxide Strontium fluoride 2. Polysulfide impression material should be: poured within 30 minutes poured within 15 minutes poured within 1 hour poured immediately 3. The chamelon effect has been portrayed by which of the ceramic restorations In ceram Cerestore Dicor Cerec 4. Lower density usually means? Low strength High strength Lighter weight Low melting temperature 5. Dental porcelain is manufactured by a process known as Devitrification Crystallisation Fritting Creaming and bisque bake 6. Nodule on the intaglio surface of a casting can be prevented by Spraying a surfactant on the wax pattern before investing Wet the wax with water before investing Use of die spacer Use of a vibrator during investing of the wax pattern 7. the main advantage of a natural glaze rather than an applied glaze is that the natural glaze is easier to achieve offers best esthetics requires a lower firing temperature is more permanent 8. the restorative material having hardness nearest to that of enamel is silicate cement amalgam direct filling gold microfilled composite resin 9. Cementation failure of a prosthesis cemented with Zinc Polycarboxylate occurs at: Between cement layer In the prosthesis itself Cement tooth interface Cement and prosthesis interface 10. Temp at which tertiary amine activates benzoyl peroxide release free radicals 60?C 50?C 25? C 37?C 11. Suck back porosity is caused by Improper venting of wax Attaching sprue in proximal surfaces Improper removal of gas Hot metal impinging on the mold surface to cause a hot spot 12. If gold content of the alloy decreases: Both strength and ductility decreases Strength decreases, ductility increases Both strength and ductility increases Strength increases, ductility decreases 13. When using which impression material can you delay pouring up of the model for up to one week? Polyether poly vinyl siloxane reversible hydrocolloid polysulfide 14. The process by which a casting is heated in a porcelain furnace to a temperature of 980″C to burn off any remaining impurities prior to adding porcelain is called: pickling degassing investing quenching 15. hydrocolloid impression material may experience all of the following except hysteresis recrystallsation syneresis imbibitions 16. an advantage of rubber base impression material over reversible hydrocolloid material is that rubber base impression material is more accurate if saliva mucus or blood is present is significantly more accurate requires less armamentarium will displace soft tissue 17. Which impression material is radio opaque: Poly ether Condensation silicone Polysulfide Addition silicone 18. the primary oxygen scavenger in noble metal casting alloy is silver iron copper zinc 19. Green shrinkage seen in : Gypsum Bonded investment It is seen in all types of investments Phosphate Bonded Investment Ethyl Silicate bonded investment 20. type IV gold casting alloys are used for fabricating removable partial denture frameworks short span bridges inlays 3/4 crowns Loading … Question 1 of 20
