Biomaterial Test 0% 5 votes, 5 avg 0 You will have 60 minutes to complete all the questions. After the timer reaches 60 minutes, the exam will end and be saved automatically. Good luck! *Fingers crossed* The timer has been reached. The exam has now been terminated and saved. Biomaterial Test 1 / 60 Elgiloy arch wire is 😕 a. Gold alloy b. Cobalt-chromium-nickel alloy c. Optical fiber arch wire d. β-titanium arch wire 2 / 60 Impression plaster is a 😕 a. Mucocompressive material b. Thermoplastic material c. Reversible impression material d. Mucostatic material 3 / 60 The most commonly used implant type presently is 😕 a. Subperiosteal b. Intramucosal implant c. Transosteal implant d. Endosseous 4 / 60 A measure of ductility of a material is referred to as 😕 a. Percentage elongation b. Proportional limit c. Yield strength d. Flexibility 5 / 60 Which of the following statements is true regarding zinc phosphate cement ? a. Is used as a permanent restorative material in adults b. Is the oldest luting agent c. Has an obtudant effect on the pulp d. The least irritant to the pulp 6 / 60 Which one of the following is not true about high-copper dental amalgam restorations ? a. Restorations are more brittle than low-copper versions b. Better corrosion resistance than low-copper dental amalgams c. Contain both Sn and Ag in the composition as well d. Produce excessive creep 7 / 60 Which of the following composites give rough surfaced finish ? a. Conventional composites b. Small particle filled composites c. Hybrid composites d. Microfilled composites 8 / 60 A glaze is placed over the finished composite restoration to 😕 a. To reduce surface porosities b. Create a rough surface that is less receptive to extrinsic stain and plaque retention c. No provide a better peripheral seal d. To change the shade 9 / 60 Which of the following statements about compomers are true ? a. They also are know as GIC b. Because of their resin content, they require a bonding agent for adhesion to tooth structure. c. They are two-paste systems that self-cure within 2 to 3 minutes. d. They typically are recommended for class II restorations. 10 / 60 All of the following are properties of Co-Cr-Ni wires except 😕 a. They have excellent tarnish and corrosion resistance b. They can be heat treated c. Their hardness is comparable to stainless steel d. They cannot be soldered or welded 11 / 60 Zinc oxide eugenal impression should be removed from oral cavity : a. When the material cannot be intended by a blunt instrument b. When it can be easily indented by a blunt instrument c. When the material is glossy d. Exactly after four minutes after kneading 12 / 60 Sulfur contamination from natural latex gloves inhibits the setting of 😕 a. Alginate b. Zinc oxide eugenol impression paste c. Polyvinyl siloxane d. Polyether 13 / 60 The cavity for a GIC restoration is preconditioned with 😕 a. Polyacrylic acid for 60 seconds b. Phosphoric acid for 60 seconds c. Polyacrylic acid for 10 seconds d. Phosphoric acid for 10 seconds 14 / 60 Which of the following material has a high coefficient of thermal expansion ? a. Unfilled acrylic resin b. Glass ionomer cement c. Composite resin d. Silicate cement 15 / 60 The type of stress to which dental amalgam is more resistant to 😕 a. Shear stress b. Compressive stress c. Impact stress d. Tensile stress 16 / 60 Stiffness of the material with passage of time is maximum in 😕 a. Polyether b. Condensation silicones c. Addition silicones d. Polysulfides 17 / 60 KHN of enamel is 😕 a. 600 b. 300 c. 100 d. 90-100 18 / 60 Which has the highest viscoelastic property and requires more time to recover from deformation ? a. Condensation silicone b. Polysulfide c. Addition silicone d. Polyether 19 / 60 Which of these statements apply to the filler particles of composites ? a. All are correct b. Microfilled composites contain more filler than all-purpose composites. c. Microfilled d. Microhybrid composites contain as much as 84% filler by weight. 20 / 60 Which of the following is called periphery wax ? a. Utility wax b. Bite registration wax c. Beading wax d. Sticky wax 21 / 60 The maximum warpage of acrylic denture occurs during 😕 a. Packing b. Curing c. Polishing d. Deflasking 22 / 60 Spot out incorrect statement regarding zinc in dentistry 😕 a. It is low in strength b. It is relatively soft and ductile c. It does not oxidize d. Pure zinc has no application in dentistry 23 / 60 Main disadvantage of laminate technique of making impression is : ? a. Difficult to manipulate b. Bond between agar and alginate is not very strong c. Cost factor is high d. Maximum details are not produced 24 / 60 Amalgam is less prone to corrosion 😕 a. If it contains zinc b. If devoid of the gamma 2 phase c. If it contains 25-27% of tin d. If it contains 4-6% of copper 25 / 60 In a porcelain fused to metal restoration, when the coefficient of thermal expansion of metal and porcelain are different 😕 a. Porcelain will not bond with metal b. Porcelain will crack on cooling c. Porcelain will wear off d. Porcelain will provide good shade 26 / 60 Main disadvantage of denture base soft reliner is 😕 a. It has not to be changed over a period of time b. It can be cleaned properly c. It can not lead to cleaned property d. It can not lead to fungal growth 27 / 60 Which of the following waxes used to align of castings before soldering ? a. Utility wax b. Sticky wax c. Base plate wax d. Carding wax 28 / 60 Cobalt-chromium alloy is mostly used for the construction of 😕 a. Intramucosal frames b. Transosteal frames c. Subperiosteal d. Endosseus implants 29 / 60 Which of the following statements about curing of composites are true ? a. Light from an argon laser will activate polymerization. b. Lights with both blue and red wavelengths are equally effective for polymerization. c. Exposure times of 2 to 3 seconds are needed for polymerization with visible light. d. Before light activation, the base and catalyst pastes are mixed. 30 / 60 Which one of the following phases in dental amalgam restoration is most prone to electrochemical corrosion ? a. Cu-Sn b. Sn-Hg c. Ag-Su d. Ag-Hg 31 / 60 In deep caities, the resin which remains unpolymerized can cause 😕 a. Sagging of restoration b. Pulp inflammation c. Porosity in restoration d. Secondary caries 32 / 60 The energy absorbed by a material when it is stressed to its proportional limit is 😕 a. Impact strength b. Resilience c. Toughness d. Flexibility 33 / 60 One of the disadvantages of using quartz as filler in restorative resin is 😕 a. It has low affinity for resin matrix b. It cause abrasion and wearing of opposing tooth surface c. It cannot be polished d. It cannot be reduced to the size of microparticle composite 34 / 60 Contamination of zinc-containing amalgam by moisture during triturating or condensation : a. Increases the setting time b. Results in a sharp decrease in flow c. Has no appreciable effect on properties except to the susceptibility to tarnish d. Results in a marked expansion 35 / 60 If the light cure resin is curd in increments, it helps in 😕 a. Achieving complete polymerization b. Compensating polymerization shrinkage c. Saving the application of bonding agent d. Providing strength to the restoration 36 / 60 Which of the following materials are used for dental implants ? a. Gold alloys b. Titanium c. Cobalt and chromium alloys d. Metal alloys 37 / 60 Color stability of cold-cured resins is inferior to that of heat cured resins due to 😕 a. Subsequent oxidation of the tertiary amine b. Increased solubility of the resin c. Decreased polymerization of the resin d. Variation in the molecular weight of the resin (low mol wt) 38 / 60 Which of the following mixing methods permits the escape of dental amalgam mercury vapor ? a. A cover over the mixing arms on a triturator b. Triturating precapsulated alloy and mercury c. Proportioning mercury and alloy into a friction-fit capsule d. Mixing in a mortar and pestle 39 / 60 Pick out the incorrect statement regarding alginate impressions 😕 a. Will be shrink as a result of syneresis b. May exhibit a fluid exudates on the surface as a result of imbibitions c. Is an irreversible hydrocolloid impression material d. Will take up water and expand if kept wet 40 / 60 Commonly used filler in composite is 😕 a. Colloidal silica b. Quartz c. Aluminum d. Glass 41 / 60 Strain that occurs when the material is stressed to its proportional limit is called 😕 a. Modulus of elasticity b. Resilience c. Flexibility d. Toughness 42 / 60 Binder in the phosphate investment is 😕 a. Phosphoric acid b. Cristobalite c. Magnesium oxide and monoammonium phosphate d. Manganese dioxide 43 / 60 When a mechanical device is used for mixing addition silicones 😕 a. Mixing time is reduced b. There is no greater uniformity in proportioning and mixing c. Mixing time is long d. More possibilities of contamination 44 / 60 Wrought metal 😕 a. Cannot be rendered corrosion resistant b. Cannot be heat treated c. Can be formed by working on a cast metal d. Can be formed by pouring molten metal into a mold 45 / 60 Which of the following statements apply to the packable composites ? a. Their depth of cure allows bulk polymerization, which has been shown to be clinically effective. b. Radiopaque c. They are radiolucent. d. Their wear rate is low (3.5 μm/year). Which is similar to that of amalgam. 46 / 60 Which of these statements are correct in terms of preparing a correctly triturated mass of amalgam ? a. An overmixed mass is removed readily from the capsule but is soupy in appearance. b. Dental amalgam is a mixture of silver alloys and mercury. c. A correctly triturated mass is a smooth homogeneous, and dull. d. An undertriturated mass is crumbly and dull. 47 / 60 Which of the following composite is recommended for non stress bearing anterior restoration ? a. Conventional composites b. Small particles c. Hybrid composites d. Microfilled composites 48 / 60 The primary difference between low- and high-copper amalgams is which of the following ? a. The amount of copper and silver b. The amount of copper and zinc c. The amount of copper and tin d. The amount of copper 49 / 60 The constituent that acts as a binder in the investment is 😕 a. Silica b. Gypsum c. Quartz d. Water 50 / 60 Stearic acid in impression compound 😕 a. Reduces plasticity b. Increase setting time c. Reduces flow d. Reduces brittleness 51 / 60 Distortion on removal from undercuts in addition silicones is very less due to 😕 a. Shrinkage of material b. Increased strain rate on unset material c. Lowest strain in compression d. Stiffness of the material 52 / 60 Which of the following is a measure of resistance to fracture ? a. Toughness b. Springiness c. Hardness d. Brittleness 53 / 60 Which of the following sentences describes the construction of removable partial dentures ? a. Carbone steal b. Artificial waxes teeth are attached c. They are removable and attached to teeth with clasps. d. They are attached to natural teeth with cements, 54 / 60 Most common use of Zinc oxide eugenol paste 😕 a. As interocclusal record material b. Dual impression for Partially edentulous patients c. Surgical paste d. Wash impression for edentulous patients 55 / 60 Acrylic resins are used in which of the following ? a. Denture bases b. Posterior inlays c. Ceramic ( porcelain )-fused-to-metal crowns d. Anterior onlays 56 / 60 A full crown on a maxillary anterior tooth may be restored with which of the following restorative materials ? a. Composite resin b. Ceramic c. Amalgam d. Gold alloys 57 / 60 Porosity in denture base resins can be due to 😕 a. Adequate mixing of liquid and powder components b. Excess heating of resin above its boiling point c. Applying sufficient pressure during polymerization d. Well flasking of wax pattern 58 / 60 Once amalgamation has occurred, which of the following is true of mercury ? a. Can form at the surface of amalgam restorations if heated to 0° C b. Is combined primarily with silver c. Has the toxic properties of unreacted mercury d. Composite restorative resins 59 / 60 Oil of clove is sometimes used in preference to eugenal in ZOE paste because : a. It increases mixing property of paste and therefore improves impression recorded b. Reduces burning sensation of paste c. Has a better reaction with zinc oxide d. To increase setting time 60 / 60 The impression material which is routinely used in auto mixing devicee system is 😕 a. Polyvinyl siloxane b. Polysulfied c. Polyether d. Condensation silicone Your score isThe average score is 0% Facebook 0% Restart quiz Any comments? Send feedback
