1. test used to check setting time of impression material isrockwell testvickers testcold bend testvicat testQuestion 1 of 20 2. Fins and spines in casting are caused by:Prolonged heatingRapid heating of investmentWater film presentIncreased casting pressureQuestion 2 of 20 3. Which of the following cannot be used for debridement of zirconia implant surfaceHi grade plastic instrumentStainless steel instrumentGold tip instrumentTitanium coated instrumentQuestion 3 of 20 4. Brush heap structure is seen in:Addition siliconesAlginateImpression compoundPolyethersQuestion 4 of 20 5. a thinner mix of gypsum bondeded investment will result inincreases thermal expansionproduce a smoother castingincreases setting expansiondecrease setting expansionQuestion 5 of 20 6. Cementation failure of a prosthesis cemented with Zinc Polycarboxylate occurs at:Cement and prosthesis interfaceBetween cement layerIn the prosthesis itselfCement tooth interfaceQuestion 6 of 20 7. Which of the following is a resorbable Bio- ceramic?CarbonCalcium phosphateZirconiaAluminaQuestion 7 of 20 8. With which of the following impression materials is it advisable to wait 20 to 30 minutes before pouring of models for stress relaxation to occur?condensation siliconesPolysulfidespolyetherspolyvinyl siloxanesQuestion 8 of 20 9. Animal test used to check biocompatibility of dental material is all exceptAme's testImplantation testbuehlar testLD50 testQuestion 9 of 20 10. Transformation toughening of zirconia occurs due to change in phase from:Cubic to tetragonalTetragonal to monoclinicMonoclinic to tetragonalAustenitic to martensitiQuestion 10 of 20 11. Which of the following is true statements regarding the polishing of amalgam?it prevents tarnishing of the restorationit should be done about 10 minutes after placementocclusion should not be checked prior to polishingit should be done with a dry polishing powderQuestion 11 of 20 12. All of the following statements are true regarding glass ionomer restorations,exceptthe best surface finish for a glass ionomer restoration is that obtained against a surface matrixglass ionomer is often the ideal material of choice for restoring root surface caries in patients with high caries activityglass ionomers are somewhat esthetic and polish much better than compositesglass ionomer adheres to mineralized tooth tissueQuestion 12 of 20 13. the union of metal to porcelain fused restoration is bycobalt and porcelaintin and indium oxidesnickel and orcelainmechanically rough surfaceQuestion 13 of 20 14. most common reason for incomplete casting when using a centrifugal casting machine ishollow spacelarge reservoirnarrow sprueincreased porosity of the investmentQuestion 14 of 20 15. metal ceramic restorations may fail due to fracture of the ceramic material .this can be best avoided ifthe casting is designed to reduce stress concentration in the ceramic materialthe ceramic material is at least 1.5 mm thickthe metal is not over 0.5 mm thickocclusal forces are minimalQuestion 15 of 20 16. Structural durability is a?None of the aboveStructural phenomenonBiological phenomenonMechanical phenomenonQuestion 16 of 20 17. nickel in high percentages in noble metal dental casting alloysdecreases tarnish resistanceincreases ductilityall of the abovedecreases strengthQuestion 17 of 20 18. role if indium in amalgam isto reduce release of mercury during amalgam polishingto reduce formation of gamma 2 phaseto reduce formation of gamma phaseto reduce elease of mercury during masticationQuestion 18 of 20 19. for best results when using an elastic impression material the prepared tooth should becovered thinly with a waer soluble lubricantcovered with a surface tension reducing agent or air driedfree of surface moisturevery dryQuestion 19 of 20 20. the restorative material having hardness nearest to that of enamel issilicate cementdirect filling goldmicrofilled composite resinamalgamQuestion 20 of 20 Loading...
