1. Most common accelerator used in gypsum is: Sodium Chloride 1 % potassium sulphate 2% sodium sulphate 2% potassium sulphate 2. what filler is used in impression compound “alginate” sodium phosphate calcium alginate sodium bicarbonate diatomaceous earth 3. Soldering flux is composed of all of the following EXCEPT one. Which one is the EXCEPTION? sodium pyroborate alum silica borax 4. Stain removing commercial denture cleanser usually contain Sodium hypochlorite Sodium perborate Soda ash Potassium perborate 5. Contact angle between liquid and adherend surface is 180 degree. This suggests none of the above Completely non wetting Good wetting Poor wetting 6. the process of driving off the water of crystallisation of gypsum to manufacture powders of plaster and stone is called sintering calcining crazing fusing 7. Gutta percha, stearic acid and shellac are added to impression compound to: To improve softness at melting temperature To prevent leaching out ofthermolabile components Improve workability & plasticity To increase stifthess and hardness of the compound 8. Clinical appearance of GIC is dictated by Particle size of powder Acid content of liquid Chemical composition of cement Viscosity of liquid 9. Following is added to zinc polycarboxylate to improve its manageability: Stannous fluoride Aluminium oxide Magnesium oxide Strontium fluoride 10. test used to check setting time of impression material is vicat test vickers test rockwell test cold bend test 11. The process in which a solid melts into a liquid with a separate crystalline phase is known as: Sintering Ceramming Incongruent melting Congruent Melting 12. In relation to gypsum products, prolonged spatulation time will lead to Increase in hardness Reduced setting time Increase in hygroscopic expansion Increase compressive strength 13. Shrinkage porosity is related to Molten metal Inlay wax Temperature Sprue size 14. which of the following will form a peritectic alloy silver and copper silver and tin silver and palladium silver and gold 15. Stiffness is: Relative hardness of a material Ability to be drawn into wires Ability to resist deformation Relative softness of material 16. Polishing agent which is known as whitening agent Chromium oxide Iron oxide None of the above Rouge 17. Modulus of elasticity/tensile strength of brittle materials is measured by 3-point bend test Diametrical compresssion test Charpy test Cold bend test 18. the antiflux used for gold solders is titanium silicon cryolite graphite 19. nickel in high percentages in noble metal dental casting alloys decreases tarnish resistance all of the above decreases strength increases ductility 20. Least amount of mercury is required in Lathe cut Hybrid Admixed Spherical Loading … Question 1 of 20
