Biomaterial Test 0% 5 votes, 5 avg 529 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 Thermal conductivity is proportional to 😕 a. Fusion temperature b. Area of conduction c. Type of metal d. Hardness of metal 2 / 60 Strain that occurs when the material is stressed to its proportional limit is called 😕 a. Flexibility b. Resilience c. Modulus of elasticity d. Toughness 3 / 60 In UV curing system the activator employed is 😕 a. Benzoin methyl ether b. Dibutyl phthalate c. Methyl methacrylate d. Hydroquinone 4 / 60 Which one of the following office conditions minimize the health hazard from spilled mercury ? a. Baseboard heating b. fluorite release c. Amalgam scrap stored in a closed container d. Floor carpeting 5 / 60 Impression compound is characterized by 😕 a. Amorphous in nature with high thermal conductivity b. Crystalline in nature with definite melting point c. Crystalline in nature with high thermal conductivity d. Amorphous in nature with low thermal conductivity 6 / 60 In alginate impression the final gel is 😕 a. Sodium alginate b. Calcium alginate c. Sodium sulphate d. Calcium sulphate 7 / 60 Greater ratio fo zinc oxide to eugenol will have the following effect on setting time 😕 a. Does not alter setting time b. Increases setting time c. Decreases setting time d. Depends on rate of mixing 8 / 60 Zinc oxide eugenal impression should be removed from oral cavity : a. Exactly after four minutes after kneading b. When the material is glossy c. When the material cannot be intended by a blunt instrument d. When it can be easily indented by a blunt instrument 9 / 60 One of the following statements which one is incorrect regarding polyether : a. The base paste consists of polyether polymer b. The main chain consists of copolymer of methylene oxide and tetrahydrofuran c. The main chain of polyether consists of copolymer of ethylene oxide and tetrahydrofuran d. Aromatic sulfonate ester acts as a cross linking agent 10 / 60 Higher mercury left in an amalgam leads to which of the following ? a. Higher creep b. Higher strength c. High corrosion d. Low corrosion 11 / 60 The energy absorbed by a material when it is stressed to its proportional limit is 😕 a. Flexibility b. Resilience c. Impact strength d. Toughness 12 / 60 Wet porcelain is condensed properly before firing to enhance all the properties except : ? a. Reduce firing shrinkage b. Reduce brittleness c. increase strength d. Reduce porosity 13 / 60 Ideally, the set amalgam should do which of the following ? a. Properties of amalgam b. Expand greatly to provide marginal seal against the tooth c. Shrink significantly to provide space for correction products to seal the margins d. Have little dimensional change 14 / 60 Which of the following waxes used to align of castings before soldering ? a. Base plate wax b. Sticky wax c. Carding wax d. Utility wax 15 / 60 The physical property measured in terms of the deformation of the structure per until dimensions is ? a. Space lattice b. Stress c. Strain d. Amorphous material 16 / 60 Which of the following base is contraindicated for composites ? a. Calcium hydroxide b. Zinc phosphate c. Zinc oxide eugenol d. Glass ionomer cement 17 / 60 An anterior fixed partial denture could have facings constructed of which of the following materials ? a. Silver alloys b. Ceramic c. Amalgam d. Gold alloy 18 / 60 A direct restorative material used frequently to restore a portion of a posterior tooth that is subject to large biting forces would possess which of the following properties ? a. Thermal insulation b. Esthetics c. High strength d. Ease of casting 19 / 60 Hand instruments for composites are made of 😕 a. Stainless steel b. Titanium c. Carbon steel d. Teflon-coated metal 20 / 60 Of the four types of gold casting alloys, the most commonly used for crowns and bridges is 😕 a. Type III b. Type II c. Type IV d. Type I 21 / 60 Which of the following is a measure of resistance to fracture ?: a. Hardness b. Springiness c. Toughness d. Brittleness 22 / 60 Contamination of zinc-containing amalgam by moisture during triturating or condensation : a. Results in a marked expansion b. Results in a sharp decrease in flow c. Increases the setting time d. Has no appreciable effect on properties except to the susceptibility to tarnish 23 / 60 A small portion of an anterior tooth would most likely be restored with which of the following ? a. Gold alloy b. Amalgam c. Porcelain d. Composite resin 24 / 60 Setting of plaster of Paris is a result of 😕 a. Interaction between hemihydrates and water b. Solubility difference between hemihydrates and dehydrate c. Loss of water from hemihydrates d. Indirect interaction between hemihydrates 25 / 60 The most effective cement in stimulating tertiary dentin is 😕 a. Calcum hydroxide b. Polycardoxylate c. Zinc silicophoshpate d. Zinc phosphate 26 / 60 All are properties of waxes except 😕 a. Creep b. Plastic deformation c. Solidification shrinkage d. Flow 27 / 60 When the gold content of gold alloys increases 😕 a. The corrosion resistance increases b. The percentage elongation decrease c. The hardness decrease d. Ductility decrease 28 / 60 The appropriate proportion of polymer to monomer component of dental resin by volume is generally 😕 a. 3:1 b. 1:3 c. 2:1 d. 1:2 29 / 60 Silver has all the following characteristics except 😕 a. Whitens when added to alloys b. Silver points serve as a root canal filling material c. Addition of palladium to silver increases corrosion d. Silver in pure form is not used in dental restorations 30 / 60 Following are the functions of impression compound except 😕 a. To make impression of edentulous ridge b. To make individual die impression with copper band c. To record mucostatic impressions d. To make special tray for final impression 31 / 60 The maximum warpage of acrylic denture occurs during 😕 a. Packing b. Curing c. Deflasking d. Polishing 32 / 60 Which of the following initiator-accelerator systems is needed for a light-activated composite? a. Organic acid-peroxide b. Diketone-amine c. Peroxide-amine d. Organic acid-metal ion 33 / 60 Full denture bases are usually made from which of the following materials ? a. Composite restorative resins b. Gold alloys c. Ceramic d. Acrylic resin 34 / 60 Which of the following composites give rough surfaced finish ? a. Microfilled composites b. Small particle filled composites c. Conventional composites d. Hybrid composites 35 / 60 Sulfur contamination from natural latex gloves inhibits the setting of 😕 a. Zinc oxide eugenol impression paste b. Alginate c. Polyether d. Polyvinyl siloxane 36 / 60 The impression material which is routinely used in auto mixing devicee system is 😕 a. Condensation silicone b. Polyvinyl siloxane c. Polyether d. Polysulfied 37 / 60 Which of the following materials are used for dental implants ? a. Gold alloys b. Titanium c. Cobalt and chromium alloys d. Metal alloys 38 / 60 Crystalline materials have 😕 a. No well-defined melting b. Well-defined melting c. Less stable space lattice d. No space lattice 39 / 60 The desirable quality of porcelain is 😕 a. Translucency b. Requirement of color c. Toughness without brittleness d. Thermal expansion 40 / 60 Which of the following is the best choice of restorative material to achieve moderate to high strength, fluorite release, and esthetics ? a. Glass ionomer b. Composite c. Compomer d. Hybrid ionomer 41 / 60 Dental personnel can do which one of the following to limit their exposure to mercury ? a. Avoid polishing amalgams b. Sterilize amalgam scrap c. Vacuum up a spill immediately d. Avoid touching freshly mixed amalgam 42 / 60 The main ingredient of casting waxes is 😕 a. Candellila wax b. Carnauba wax c. Paraffin wax d. Gum dammar 43 / 60 Biting force in the molar region ranges from 😕 a. 900-1000 N b. 400-890 N c. 600-1000 N d. 1000-1300 N 44 / 60 Materials having coefficient of thermal expansion close to the tooth structure 😕 a. Glass ionomer cement b. Amalgam c. Silicate cement d. Unfilled 45 / 60 Potato starch is contained in which impression material ? a. Impression plaster b. Agar agar c. Impression compound d. Potassium sulfate 46 / 60 An anterior fixed partial denture could have facings constructed of which of the following materials ? a. Composite resin b. Metal c. Gold alloy d. Amalgam 47 / 60 Which one of the following is not true about high-copper dental amalgam restorations ? a. Contain both Sn and Ag in the composition as well b. Produce excessive creep c. Restorations are more brittle than low-copper versions d. Better corrosion resistance than low-copper dental amalgams 48 / 60 Which of the following statements about adhesion of composite restorations to tooth structure are true ? a. Bonding is achieved to enamel by application of an acid etchant followed by application of a bonding agent and then the composites resin. b. The bonding agent forms a hybrid layer with enamel. c. The bonding agent forms a micromechanical bond with enamel but a chemical bond with dentin. d. Most bonding agent bond more effectively to a dry tooth surface. 49 / 60 Nickel sensitivity in the general population is 😕 a. 3% for men b. 3% for women c. 1% in the overall population d. 11% for women 50 / 60 Which of the following phases in dental amalgam restoration is most prone to electrochemical properties ? a. Sn-Hg b. Ag-Sn c. Ag-Hg d. Cu-Sn 51 / 60 Which of the following occurs when dental amalgam is overmixed ? a. Corrosion decreases b. Compressive strength decreases c. Corrosion increases d. Tensile strength increases 52 / 60 Which of the following waxes is obtained from distillation of petroleum ? a. Carnauba and candellia b. Montan and Japan coco c. Paraffin and microcrystalline wax d. Spermitic and bees wax 53 / 60 Commonly used coloring agent in impression plaster is 😕 a. Indigo dye b. Congo red c. Alizarin red d. Metallic oxide 54 / 60 Which of the following statements is true regarding zinc phosphate cement ? a. Is the oldest luting agent b. Has an obtudant effect on the pulp c. The least irritant to the pulp d. Is used as a permanent restorative material in adults 55 / 60 The main advantage of composites compared to silicates cement is 😕 a. Color matching with the tooth structure is excellent b. Practically insoluble in oral fluids c. High modulus of resilience d. Coefficient of thermal expansion close to tooth structure 56 / 60 Which of the composites with the following fillers may be radiopaque ? a. Colloidal silica b. Barium glass c. Lithium aluminum silicate d. Quartz 57 / 60 Which of the following statements about laboratory composites are true ? a. Bridge prepared from laboratory composites require a metal substructure. b. Restorations prepared from laboratory composites typically are cemented with zinc phosphate cement. c. Fiber reinforcement increases their strength but decrease their rigidity. d. Curing using light, heat, and pressure increase the wear resistance. 58 / 60 Spot out incorrect statement regarding zinc in dentistry 😕 a. Pure zinc has no application in dentistry b. It does not oxidize c. It is relatively soft and ductile d. It is low in strength 59 / 60 One of the following statements which one is incorrect regarding addition silicones 😕 a. Undetectable distortion on removal b. No evolution of any byproduct under all circumstances c. Can be used in automixing devices d. Dimensionally stable even after 1 week 60 / 60 The physical properties most desirable in set amalgam are which of the following ? a. Higher strength, high creep, high corrosion b. Higher strength, low creep, low corrosion c. Higher strength, high creep, low corrosion d. Low strength, low creep, low corrosion Your score isThe average score is 85% Facebook 0% Restart quiz Any comments? Send feedback
