1. Cutting edge of surgical burs are made from martensite form rather than austenite form due to which of the following reasonMartensite form has less strengthMartensite form is very brittleMartensite form is corrosion resistantMartensite form is hardQuestion 1 of 20 2. the primary oxygen scavenger in noble metal casting alloy issilverironzinccopperQuestion 2 of 20 3. By product of setting reaction of condensation silicon:AcetoneWaterHydrogenEthyl alcoholQuestion 3 of 20 4. gold alloys used for the fabrication of saddle bars and clasps aretype IItype IIItype IVtype IQuestion 4 of 20 5. Hardening heat treatment for gold copper alloys involvesQuenching immediately after castingHeating to 350 degree C for 15-30 min followed by quenchingQuenching immediately after recrystallisationHeating to 700 degree C for 10 min followed by quenchingQuestion 5 of 20 6. Disinfection of alginate impressions when immersion method is used should not exceed10m5m30m20mQuestion 6 of 20 7. Transformation toughening of zirconia occurs due to change in phase from:Monoclinic to tetragonalCubic to tetragonalTetragonal to monoclinicAustenitic to martensitiQuestion 7 of 20 8. In relation to gypsum products, prolonged spatulation time will lead toIncrease in hardnessIncrease in hygroscopic expansionIncrease compressive strengthReduced setting timeQuestion 8 of 20 9. Stain removing commercial denture cleanser usually containSodium perboratePotassium perborateSoda ashSodium hypochloriteQuestion 9 of 20 10. an advantage of rubber base impression material over reversible hydrocolloid material is that rubber base impression materialrequires less armamentariumis significantly more accuratewill displace soft tissueis more accurate if saliva mucus or blood is presentQuestion 10 of 20 11. Phosphate bonded investment is made carbon free:To prevent staining of ceramicFor easier divesting of investmenTo prevent brittleness of alloyTo produce smooth castingQuestion 11 of 20 12. the union of metal to porcelain fused restoration is bynickel and orcelainmechanically rough surfacecobalt and porcelaintin and indium oxidesQuestion 12 of 20 13. Not associated with corrosion products in metal alloysChloridesCarbonatesOxidesSulphidesQuestion 13 of 20 14. most common reason for incomplete casting when using a centrifugal casting machine ishollow spacenarrow spruelarge reservoirincreased porosity of the investmentQuestion 14 of 20 15. Young's modulus is defined as:Area under the stress strain curve till point of fractureStress/strain above elastic limitStress/strain below elastic limitLimit where a material shows plastic defonnationQuestion 15 of 20 16. maximum shrinkage of firing of ceramic occurs during which stagemedium bisquehigh bisquenone of the abovelow bisqueQuestion 16 of 20 17. the main advantage of a natural glaze rather than an applied glaze is that the natural glazeis easier to achieveis more permanentrequires a lower firing temperatureoffers best estheticsQuestion 17 of 20 18. Which of the following cements provide maximum resistance to decalcification while placing bands on molarSilicateGICZinc phosphatePolycarboxylateQuestion 18 of 20 19. the restorative material having hardness nearest to that of enamel ismicrofilled composite resinamalgamsilicate cementdirect filling goldQuestion 19 of 20 20. self curing acrylics for tooth restorations are least compatible with which materialeugenolcopal varnishcalcium hydroxidealcoholQuestion 20 of 20 Loading...