Biomaterial Test

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Biomaterial Test

1 / 60

The most effective cement in stimulating tertiary dentin is 😕

a. Polycardoxylate

b. Zinc phosphate

c. Zinc silicophoshpate

d. Calcum hydroxide

2 / 60

In a porcelain fused to metal restoration, when the coefficient of thermal expansion of metal and porcelain are different 😕

a. Porcelain will wear off

b. Porcelain will crack on cooling

c. Porcelain will provide good shade

d. Porcelain will not bond with metal

3 / 60

The constituent that acts as a binder in the investment is 😕

a. Quartz

b. Water

c. Silica

d. Gypsum

4 / 60

Compared to lathe-cut alloy, spherical dental amalgam alloys 😕

a. Requires less amalgamation time

b. Have longer setting time

c. Requires more mercury for trituration

d. Requires higher forces of condensation

5 / 60

A full crown on a maxillary anterior tooth may be restored with which of the following restorative materials ?

a. Amalgam

b. Ceramic

c. Gold alloys

d. Composite resin

6 / 60

Commonly used filler in composite is 😕

a. Glass

b. Colloidal silica

c. Aluminum

d. Quartz

7 / 60

Impression plaster is a 😕

a. Thermoplastic material

b. Mucostatic material

c. Mucocompressive material

d. Reversible impression material

8 / 60

Stiffness of the material with passage of time is maximum in 😕

a. Addition silicones

b. Polysulfides

c. Condensation silicones

d. Polyether

9 / 60

All are properties of waxes except 😕

a. Creep

b. Flow

c. Solidification shrinkage

d. Plastic deformation

10 / 60

An anterior fixed partial denture could have facings constructed of which of the following materials ?

a. Amalgam

b. Silver alloys

c. Gold alloy

d. Ceramic

11 / 60

The main use of zinc oxide eugenol cement is 😕

a. Indirect pulp capping agent

b. Permanent restoration

c. Temporary restoration

d. Base

12 / 60

Impression compound is characterized by 😕

a. Crystalline in nature with definite melting point

b. Crystalline in nature with high thermal conductivity

c. Amorphous in nature with high thermal conductivity

d. Amorphous in nature with low thermal conductivity

13 / 60

Which of these statements apply to the filler particles of composites ?

a. Microfilled

b. Microhybrid composites contain as much as 84% filler by weight.

c. Microfilled composites contain more filler than all-purpose composites.

d. All are correct

14 / 60

The most commonly employed alloy combination for use in implants is 😕

a. Titanium-molybdenum-vanadium alloy

b. Titanium-platinum-aluminum alloy

c. Platinum-aluminum-vanadium alloy

d. Titanium-aluminum-vanadium alloy

15 / 60

Which of the following properties of calcium hydroxide cement help in the formation of reparative dentin ?

a. No antibacterial action

b. High alkalinity

c. Low alkalinity

d. No Protein lysing effect

16 / 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

17 / 60

Softening of impressing compound is best accomplished by 😕

a. Water bath

b. Oil bath

c. Open flame

d. Dry heat

18 / 60

Which of the following phases in dental amalgam restoration is most prone to electrochemical properties ?

a. Cu-Sn

b. Ag-Hg

c. Ag-Sn

d. Sn-Hg

19 / 60

Which of the following initiator-accelerator systems is needed for a light-activated composite?

a. Organic acid-metal ion

b. Diketone-amine

c. Organic acid-peroxide

d. Peroxide-amine

20 / 60

Strength of dental porcelain is dependent on 😕

a. Composition

b. Resistance to fusion

c. Rough

d. No internal structure

21 / 60

Inorganic phase in a composite matrix 😕

a. Increases the polymerization shrinkage

b. Decreases the mechanical strength

c. Increases coefficient of thermal expansion

d. Increases the mechanical strength

22 / 60

Hand instruments for composites are made of 😕

a. Carbon steel

b. Titanium

c. Teflon-coated metal

d. Stainless steel

23 / 60

In dental plaster the main ingredient is 😕

a. Calcium sulfate dehydrate

b. Calcium anhydrate

c. Calcium phosphate

d. Calcium sulfate hemihydarate

24 / 60

A potentially toxic element in base metal alloys is 😕

a. Beryllium

b. Molybdenum

c. Boron

d. Magnesium

25 / 60

Which of the following mixing methods permits the escape of dental amalgam mercury vapor ?

a. Proportioning mercury and alloy into a friction-fit capsule

b. Triturating precapsulated alloy and mercury

c. A cover over the mixing arms on a triturator

d. Mixing in a mortar and pestle

26 / 60

The physical property measured in terms of the deformation of the structure per until dimensions is ?

a. Strain

b. Space lattice

c. Stress

d. Amorphous material

27 / 60

Conventional dental amalgam alloy contains 😕

a. Silver, tin, palladium and zinc

b. Silver, mercury, copper and mercury

c. Silver, mercury, copper and zinc

d. Silver, tin, copper and zinc

28 / 60

Minimal thickness of base for adequate thermal insulation is 😕

a. 1 mm

b. 2 mm

c. 0.75 mm

d. 0.5 mm

29 / 60

Glass ionomer cenment is not recommended for 😕

a. Class III restoration

b. Class V restoration

c. Class IV resoration

d. Class I restoration

30 / 60

Thermal conductivity is proportional to 😕

a. Type of metal

b. Hardness of metal

c. Fusion temperature

d. Area of conduction

31 / 60

Calcium hydroxide is used for 😕

a. Reduce maginal leakage

b. Reinforce the restoration

c. Pulp capping

d. To prevent recurrent caries

32 / 60

Most common use of Zinc oxide eugenol paste 😕

a. Dual impression for Partially edentulous patients

b. As interocclusal record material

c. Wash impression for edentulous patients

d. Surgical paste

33 / 60

Materials having coefficient of thermal expansion close to the tooth structure 😕

a. Unfilled

b. Silicate cement

c. Glass ionomer cement

d. Amalgam

34 / 60

The fluoride release from glass ionomer cement is 😕

a. 0.0005 mg during the first month

b. 0.75 mg during the first week

c. 0.005 mg during the first week

d. 0.075 mg during the first month

35 / 60

The main function of zinc in amalgam is 😕

a. To increase the longevity of amalgam after setting

b. To produce delayed expansion

c. To prevent the creep

d. To increase the shelf-life of an amalgam

36 / 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. High strength

b. Thermal insulation

c. Esthetics

d. Ease of casting

37 / 60

Which of the following statements about adhesion of composite restorations to tooth structure are true ?

a. Most bonding agent bond more effectively to a dry tooth surface.

b. Bonding is achieved to enamel by application of an acid etchant followed by application of a bonding agent and then the composites resin.

c. The bonding agent forms a hybrid layer with enamel.

d. The bonding agent forms a micromechanical bond with enamel but a chemical bond with dentin.

38 / 60

Gypsum investments should not be heated above 😕

a. 10000C

b. 7000C

c. 17000C

d. 4500C

39 / 60

In a porcelain fused to metal restoration, the porcelain is-bonded to metal by 😕

a. High malleafility of metal

b. Chemical bonding

c. Chemico-mechenical bonding

d. Hight ductility of metal

40 / 60

The gelation temperature of agar hydrocolloid impression material should be 😕

a. 45-600C

b. 37-450C

c. Far below the oral temperature

d. 100C higher than mouth temperature

41 / 60

The temperature at which a solid changes into liquid is called 😕

a. Temperature of vaporization

b. Latent heat

c. Fusion temperature

d. Specific temperature

42 / 60

Elgiloy arch wire is 😕

a. Optical fiber arch wire

b. β-titanium arch wire

c. Cobalt-chromium-nickel alloy

d. Gold alloy

43 / 60

Condensation of porcelain is done by all the methods except 😕

a. Spatulation method

b. Ceramming method

c. Brush addition technique

d. Vibration method

44 / 60

Commonly used coloring agent in impression plaster is 😕

a. Metallic oxide

b. Congo red

c. Indigo dye

d. Alizarin red

45 / 60

Crystalline materials have 😕

a. Less stable space lattice

b. No well-defined melting

c. No space lattice

d. Well-defined melting

46 / 60

The main ingredient of casting waxes is 😕

a. Carnauba wax

b. Paraffin wax

c. Candellila wax

d. Gum dammar

47 / 60

Hypersensitivity reactions like contact dermatitis is caused by 😕

a. Condensation silicones

b. Polysulfides

c. Polyether

d. Addition silicones

48 / 60

Polyether is different from other elastomers in the following aspects 😕

a. Can not be used as light cure material

b. Hydropholic in nature

c. High stiffiness

d. Low stiffness

49 / 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. Variation in the molecular weight of the resin (low mol wt)

c. Increased solubility of the resin

d. Decreased polymerization of the resin

50 / 60

The most commonly used implant type presently is 😕

a. Transosteal implant

b. Endosseous

c. Subperiosteal

d. Intramucosal implant

51 / 60

The following statements about dental porcelains are true except 😕

a. It is brittle in nature

b. Undergoes firing shrinkage

c. Crystalline nature

d. Undergoes discoloration

52 / 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. Better corrosion resistance than low-copper dental amalgams

d. Restorations are more brittle than low-copper versions

53 / 60

Which of the following is called periphery wax ?

a. Bite registration wax

b. Sticky wax

c. Beading wax

d. Utility wax

54 / 60

Which of the following waxes used to align of castings before soldering ?

a. Utility wax

b. Carding wax

c. Sticky wax

d. Base plate wax

55 / 60

An anterior fixed partial denture could have facings constructed of which of the following materials ?

a. Amalgam

b. Composite resin

c. Gold alloy

d. Metal

56 / 60

A cavity varnish used for lining the preparation for a dental amalgam restoration will :

a. Provide strength of amalgam

b. Provide electrical insulation

c. Reduce early marginal leakage tooth structure

d. Provide thermal insulation

57 / 60

Which of the following elastomers is suited for multiple cast pouring 😕

a. Condensation silicone

b. Polysulfide

c. Addition silicone

d. Polyether

58 / 60

Main disadvantage of laminate technique of making impression is : ?

a. Bond between agar and alginate is not very strong

b. Cost factor is high

c. Maximum details are not produced

d. Difficult to manipulate

59 / 60

Strain that occurs when the material is stressed to its proportional limit is called 😕

a. Resilience

b. Flexibility

c. Toughness

d. Modulus of elasticity

60 / 60

Which of the following properties would be of least importance, when selecting an impression material ?

a. Adhesion

b. Dimensional stability

c. Flow

d. Biocompatibility

Your score is

The average score is 86%

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