Biomaterial Test

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Biomaterial Test

1 / 60

Which of the composites with the following fillers may be radiopaque ?

a. Barium glass

b. Lithium aluminum silicate

c. Quartz

d. Colloidal silica

2 / 60

Gypsum investments should not be heated above 😕

a. 17000C

b. 7000C

c. 4500C

d. 10000C

3 / 60

The main use of zinc oxide eugenol cement is 😕

a. Permanent restoration

b. Base

c. Temporary restoration

d. Indirect pulp capping agent

4 / 60

Which of the following base is contraindicated for composites ?

a. Calcium hydroxide

b. Glass ionomer cement

c. Zinc oxide eugenol

d. Zinc phosphate

5 / 60

Excess composite from the labial surfaces can be removed by using 😕

a. Carbide burs at low to medium speed

b. Diamond burs at low to medium speed

c. Diamond burs at high speed

d. Carbide burs at high speed

6 / 60

Porosity in denture base resins can be due to 😕

a. Adequate mixing of liquid and powder components

b. Applying sufficient pressure during polymerization

c. Well flasking of wax pattern

d. Excess heating of resin above its boiling point

7 / 60

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

a. Ag-Su

b. Ag-Hg

c. Sn-Hg

d. Cu-Sn

8 / 60

The type of stress to which dental amalgam is more resistant to 😕

a. Compressive stress

b. Tensile stress

c. Shear stress

d. Impact stress

9 / 60

Which of the following uses a hardened steel ball indenting tool ?

a. Vichers hardness test

b. Rockwell hardness test

c. Knoop hardness test

d. Brinell hardness test

10 / 60

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

a. Triturating precapsulated alloy and mercury

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

c. A cover over the mixing arms on a triturator

d. Mixing in a mortar and pestle

11 / 60

Modifiers are added to plaster of Paris mainly to 😕

a. Reduce porosity

b. Get a smooth surface

c. Regulate the setting time

d. Increase strength

12 / 60

Sulfur contamination from natural latex gloves inhibits the setting of 😕

a. Alginate

b. Zinc oxide eugenol impression paste

c. Polyether

d. Polyvinyl siloxane

13 / 60

Porcelain-bonded to metal is stronger when fired 😕

a. Under compression

b. Several times in air

c. Under low temperature

d. After metal is tempered

14 / 60

The most effective cement in stimulating tertiary dentin is 😕

a. Polycardoxylate

b. Calcum hydroxide

c. Zinc silicophoshpate

d. Zinc phosphate

15 / 60

The product that is formed on the surface of the amalgam restoration and frequently result in discoloration is 😕

a. Sulphide

b. Gamma I Phase

c. Oxide

d. Gamma II Phase

16 / 60

Which of the following materials are used for dental implants ?

a. Cobalt and chromium alloys

b. Titanium

c. Metal alloys

d. Gold alloys

17 / 60

The gelation temperature of agar hydrocolloid impression material should be 😕

a. Far below the oral temperature

b. 45-600C

c. 37-450C

d. 100C higher than mouth temperature

18 / 60

Dispensing composite resins using a syringe is advantageous because it 😕

a. Conserves the material

b. Increases surface smoothness

c. Increases strength and abrasive resistance

d. Decreases air voids in the restoration

19 / 60

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

a. Strain

b. Space lattice

c. Amorphous material

d. Stress

20 / 60

Crystalline materials have 😕

a. Less stable space lattice

b. Well-defined melting

c. No well-defined melting

d. No space lattice

21 / 60

In an alloy oxygen scavenger is 😕

a. Zinc

b. Copper

c. Silver

d. Palladium

22 / 60

Softening of impressing compound is best accomplished by 😕

a. Dry heat

b. Water bath

c. Oil bath

d. Open flame

23 / 60

Biting force in the molar region ranges from 😕

a. 1000-1300 N

b. 400-890 N

c. 600-1000 N

d. 900-1000 N

24 / 60

Distortion on removal from undercuts in addition silicones is very less due to 😕

a. Increased strain rate on unset material

b. Shrinkage of material

c. Stiffness of the material

d. Lowest strain in compression

25 / 60

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

a. Condensation silicones

b. Polyether

c. Addition silicones

d. Polysulfides

26 / 60

In alginate impression the final gel is 😕

a. Calcium sulphate

b. Calcium alginate

c. Sodium alginate

d. Sodium sulphate

27 / 60

Commonly used viscosity controller in composites is 😕

a. TEG-DMA

b. Methyl methacrylate

c. Bis-GAM

d. Polyurethanes

28 / 60

A potentially toxic element in base metal alloys is 😕

a. Boron

b. Beryllium

c. Molybdenum

d. Magnesium

29 / 60

Cobalt-chromium alloy is mostly used for the construction of 😕

a. Endosseus implants

b. Intramucosal frames

c. Subperiosteal

d. Transosteal frames

30 / 60

One of the disadvantages of using quartz as filler in restorative resin is 😕

a. It cannot be polished

b. It cause abrasion and wearing of opposing tooth surface

c. It has low affinity for resin matrix

d. It cannot be reduced to the size of microparticle composite

31 / 60

Oxalates, carbonates, potassium, trisodium phosphates are added to alginate as 😕

a. Fillers

b. Reactors

c. Accelerators

d. Retarders

32 / 60

In the cavities which are more than 2mm deep a light-cured restoration is 😕

a. Not indicated

b. Restoration should be build in increments

c. Cured for longer period

d. Fifth generation bonding agent should be applied

33 / 60

The reason for hydroxyapatite coating on implant biomaterials is 😕

a. Prolonged healing time

b. Greater bony opposition

c. Lesser bony apposition

d. Presence of fibrous tissue

34 / 60

The reason zinc oxide eugenol cement is used as a temporary restoration 😕

a. It does not form reparative dentin

b. It has poor tensile strength

c. It has an obtudant effect

d. It does not have anticariogenic activity

35 / 60

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

a. Peroxide-amine

b. Organic acid-peroxide

c. Diketone-amine

d. Organic acid-metal ion

36 / 60

Carnauba wax is preferred to candelilla wax as 😕

a. It provides luster to the pattern

b. It is sticky

c. It has low melting temperature

d. It is harder and has less flow

37 / 60

Which of the following metals currently are used in dental alloys ?

a. Waxe

b. Glass ionomer

c. Ceramic

d. Gold

38 / 60

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

a. Carding wax

b. Sticky wax

c. Utility wax

d. Base plate wax

39 / 60

The cracks formed on the ceramic during cooling because 😕

a. The cooling of the outer and the inner layer occurs at the same rate

b. The outer layer cools more rapidly than the interior

c. The inner layer cools more rapidly than the outer layer

d. Due to external forces

40 / 60

Which of the following is a measure of resistance to fracture ?

a. Hardness

b. Brittleness

c. Toughness

d. Springiness

41 / 60

Light source in the curing unit is usually 😕

a. Infra red bulb

b. Ultraviolet light bulb

c. Tungsten halogen light bulb

d. Sun light

42 / 60

The catalyst used for condensation silicones is 😕

a. Stannous octoate

b. Platinum

c. Oleic acid

d. Lead dioxide

43 / 60

The main ingredient of casting waxes is 😕

a. Carnauba wax

b. Paraffin wax

c. Candellila wax

d. Gum dammar

44 / 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.

45 / 60

Which one of the following office conditions minimize the health hazard from spilled mercury ?

a. Baseboard heating

b. Floor carpeting

c. fluorite release

d. Amalgam scrap stored in a closed container

46 / 60

In visible light-cured composites photo initiator molecule is 😕

a. Bis-phenol-A

b. Toluidine

c. Camphoroquinone

d. Benzoyl methyl ether

47 / 60

Cavity varnish should not be applied when the following is used as a filling material 😕

a. Amalgam

b. Zinc phosphate

c. Silicate

d. Direct resin-filling material

48 / 60

The most commonly used implant type presently is 😕

a. Transosteal implant

b. Endosseous

c. Intramucosal implant

d. Subperiosteal

49 / 60

Which one of the following represents the maximum safe concentration of mercury vapor in the breathing zone for a 40-hour work week ?

a. 0.05 mg Hg/m3 of air

b. 100 mg Hg/m3 of air

c. 30 mg Hg/m3 of air

d. 0.04 mg Hg/m3 of air

50 / 60

Which of the following sentences describes the construction of removable partial dentures ?

a. They are attached to natural teeth with cements,

b. Carbone steal

c. They are removable and attached to teeth with clasps.

d. Artificial waxes teeth are attached

51 / 60

Contamination of zinc-containing amalgam by moisture during triturating or condensation :

a. Results in a sharp decrease in flow

b. Increases the setting time

c. Has no appreciable effect on properties except to the susceptibility to tarnish

d. Results in a marked expansion

52 / 60

Wet porcelain is condensed properly before firing to enhance all the properties except : ?

a. Reduce brittleness

b. Reduce firing shrinkage

c. increase strength

d. Reduce porosity

53 / 60

Clinical significance of smear layer :

a. Improve the strength of the composite

b. Provides calcium for adhesion of composites

c. Increases the bonding action of the bonding agent

d. Bonded to tooth structure and prevents composite adhesion

54 / 60

Which of the following composites give rough surfaced finish ?

a. Small particle filled composites

b. Hybrid composites

c. Microfilled composites

d. Conventional composites

55 / 60

Spot out incorrect statement regarding zinc in dentistry 😕

a. Pure zinc has no application in dentistry

b. It is relatively soft and ductile

c. It does not oxidize

d. It is low in strength

56 / 60

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

a. Gold alloys

b. Composite resin

c. Amalgam

d. Ceramic

57 / 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

58 / 60

Passiveness of chrome cobalt alloys is due to formation of 😕

a. Cobalt oxide

b. Ferric oxide

c. Chromium carbide

d. Chromium oxide

59 / 60

All are properties of waxes except 😕

a. Plastic deformation

b. Solidification shrinkage

c. Flow

d. Creep

60 / 60

The cavity for a GIC restoration is preconditioned with 😕

a. Polyacrylic acid for 10 seconds

b. Polyacrylic acid for 60 seconds

c. Phosphoric acid for 10 seconds

d. Phosphoric acid for 60 seconds

Your score is

The average score is 42%

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