1. main advantage of zinc phosphate over GIC is increased tensile strength increase modulus of elasticity increase compressive strength more biocompatibility 2. Which impression material is most difficult to remove without fracturing teeth of a stone model? Addition Silicone Polyether Condensation silicone Polysulphide 3. the prinicipal factor in minimising the firing shrinkage of porcelain is the fusion temperature uniformity of particle size thoroughness of condensation ratio of flux to feldspar 4. Effects associated with cold working i.e lowered ductility and distorted grains can be eliminated by process known as Strain hardening Annealing Eutectic Concentricity 5. Which of the following statements is not true regarding creep? creep is a process that happens over time undertrituration tends to increase the creep rate creep gradually increases the marginal integrity of an amalgam restoration increasing the condensation pressure decreases the creep rate 6. When using which impression material can you delay pouring up of the model for up to one week? Polyether polysulfide poly vinyl siloxane reversible hydrocolloid 7. the difference between heat cured and cold cured acrylic resin is least significant with respect to the property of hardness color stability internal porosity transverse strength 8. If multiple firing is done to opaque layer of dental porcelain, then it becomes? Too Smooth Too glazed Cracked Become more opaque 9. When Alginate is mixed with tap water having high calcium sulfate and magnesium, what happens Acceleration of setting reaction Weakened stone dies Retardation of setting reaction Permanent deformation of alginate 10. A base that is typically placed over a calcium hydroxide base (which has been placed over a pulp exposure); is known as: secondary base indirect base direct base primary base 11. Which of the following is used for making blades and sharp surgical instruments: Austenitic steel martensitic steel Ferrite steel none of the above 12. Lower density usually means? Lighter weight High strength Low melting temperature Low strength 13. role if indium in amalgam is to reduce formation of gamma phase to reduce elease of mercury during mastication to reduce release of mercury during amalgam polishing to reduce formation of gamma 2 phase 14. A system of manufacturing copings from blocks of pure titanium by machine duplication and spark erosion is Captek Empress Procera Inceram 15. Low-fusing porcelain is usually used for the manufacture of: all of the above all ceramic crowns denture teeth metal-ceramic crowns 16. Which of the following cannot be used for debridement of zirconia implant surface Hi grade plastic instrument Stainless steel instrument Titanium coated instrument Gold tip instrument 17. Cerrobend alloy is high fusing metal for positioning or shielding stent low fusing metal for positioning or shielding stent high fusing metal for removing memory patterns low fusing material for removing memory patterns 18. Asbestos is used as a lining in a casting ring to insulate against thermal conductivity allow for expansion of the investment. prevent fracture of the investment during heating. facilitate removal of the investment after casting. 19. Fluoride flux used in soldering works by Prevents formation of chromium oxide or dissolves already formed chromium oxide Preventing flow of solder to other areas Forms a protective film during soldering Weakens the solder joint 20. By product of setting reaction of condensation silicon: Water Ethyl alcohol Hydrogen Acetone Loading … Question 1 of 20
