Biomaterial Test

5 votes, 5 avg

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Biomaterial Test

1 / 60

Proconditioning before GIC restoration is done in order to 😕

a. Create tags

b. Remove smear layer

c. Facilitate mechanical bonding

d. Provide more strenght

2 / 60

The light from the visible light curing unit can cause 😕

a. Corneal ulceration

b. Iritis

c. Cataract

d. Retinal damage

3 / 60

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

a. Shrinkage of material

b. Stiffness of the material

c. Increased strain rate on unset material

d. Lowest strain in compression

4 / 60

Hydrocolloid impression should be removed from the mouth with a sharp jerk because 😕

a. Faster rate of removal increases the yield strength

b. The brush heap structure of a gel responds more favorably to a sudden force

c. It is the easiest method of removal

d. It decreases the time for syneresis to occur

5 / 60

If the light cure resin is curd in increments, it helps in 😕

a. Saving the application of bonding agent

b. Achieving complete polymerization

c. Providing strength to the restoration

d. Compensating polymerization shrinkage

6 / 60

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

a. Amalgam scrap stored in a closed container

b. Baseboard heating

c. Wall carpeting

d. Floor carpeting

7 / 60

The maximum warpage of acrylic denture occurs during 😕

a. Polishing

b. Packing

c. Deflasking

d. Curing

8 / 60

Softening of impressing compound is best accomplished by 😕

a. Dry heat

b. Oil bath

c. Open flame

d. Water bath

9 / 60

The reason for hydroxyapatite coating on implant biomaterials is 😕

a. Lesser bony apposition

b. Prolonged healing time

c. Greater bony opposition

d. Presence of fibrous tissue

10 / 60

In dental porcelains metallic oxides provide 😕

a. Color and increases the strength

b. Provides refractile property and increases strength

c. Color but decreases the strength

d. Color and provides refractile property

11 / 60

Most commonly used pit and fissure sealant is 😕

a. Unfilled acrylic

b. Bis-GMA resin

c. Filled acrylic

d. Polyurethane

12 / 60

Dental personnel can do which one of the following to limit their exposure to mercury ?

a. Avoid polishing amalgams

b. Avoid touching freshly mixed amalgam

c. Vacuum up a spill immediately

d. Sterilize amalgam scrap

13 / 60

Porcelain-bonded to metal is stronger when fired 😕

a. Under low temperature

b. Under compression

c. After metal is tempered

d. Several times in air

14 / 60

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

a. Hight ductility of metal

b. Chemical bonding

c. High malleafility of metal

d. Chemico-mechenical bonding

15 / 60

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

a. Requires higher forces of condensation

b. Requires more mercury for trituration

c. Have longer setting time

d. Requires less amalgamation time

16 / 60

Clinical significance of smear layer :

a. Bonded to tooth structure and prevents composite adhesion

b. Increases the bonding action of the bonding agent

c. Improve the strength of the composite

d. Provides calcium for adhesion of composites

17 / 60

The main ingredient of casting waxes is 😕

a. Carnauba wax

b. Candellila wax

c. Gum dammar

d. Paraffin wax

18 / 60

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

a. Retarders

b. Accelerators

c. Reactors

d. Fillers

19 / 60

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

a. Toughness

b. Brittleness

c. Hardness

d. Springiness

20 / 60

Wrought metal 😕

a. Can be formed by working on a cast metal

b. Cannot be rendered corrosion resistant

c. Can be formed by pouring molten metal into a mold

d. Cannot be heat treated

21 / 60

Gold casting alloys are classified as type I, II, III or IV among these, having highest hardness is 😕

a. Type IV

b. Type II

c. Type I

d. Type III

22 / 60

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

a. Glass ionomer

b. Ceramic

c. Gold

d. Waxe

23 / 60

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

a. Diamond burs at high speed

b. Carbide burs at low to medium speed

c. Diamond burs at low to medium speed

d. Carbide burs at high speed

24 / 60

Conventional dental amalgam alloy contains 😕

a. Silver, tin, palladium and zinc

b. Silver, tin, copper and zinc

c. Silver, mercury, copper and zinc

d. Silver, mercury, copper and mercury

25 / 60

The chemistry behind the condensation of the amalgam is to 😕

a. Condense the unattacked gamma particles

b. Condense the unattacked gamma II particles

c. Condense the unattacked gamma I particles

d. To reduce gamma II particules

26 / 60

Montan waxes have the following properties except 😕

a. Have low melting points of 42oC

b. Are mineral waxes

c. Hard, brittle and lustrous

d. Obtained by extraction from lignite

27 / 60

Main disadvantage of denture base soft reliner is 😕

a. It has not to be changed over a period of time

b. It can not lead to fungal growth

c. It can not lead to cleaned property

d. It can be cleaned properly

28 / 60

Adhesion in composites is due to 😕

a. True chemical bonding to tooth structure

b. Presence of smear layer

c. Mechanical interlocking

d. Cohesion

29 / 60

Ideal metal used for electroplating polysulfide impression is 😕

a. Silver

b. Nickel

c. Copper

d. Cobalt

30 / 60

Ideally, the set amalgam should do which of the following ?

a. Expand greatly to provide marginal seal against the tooth

b. Properties of amalgam

c. Shrink significantly to provide space for correction products to seal the margins

d. Have little dimensional change

31 / 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

32 / 60

Metal has the following properties except 😕

a. Electroplated silver and copper are used in dies

b. Metal is any element that ionizes positively in solution

c. Pure metals are not useful in dentistry

d. All metals do not have same degrees of strength and plasticity

33 / 60

Which one of the following phases in dental amalgam restoration has the best mechanical properties ?

a. Ag-Su

b. Ag-Hg

c. Sn-Hg

d. Cu-Sn

34 / 60

Condensation of porcelain is done by all the methods except 😕

a. Vibration method

b. Ceramming method

c. Spatulation method

d. Brush addition technique

35 / 60

Silver in the set amalgam alloy tends to have the following effect 😕

a. Produces contraction

b. Hydrolyzes the water if contaminated

c. Decreases the setting time

d. Decreases ductility

36 / 60

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

a. Knoop hardness test

b. Brinell hardness test

c. Vichers hardness test

d. Rockwell hardness test

37 / 60

Passiveness of chrome cobalt alloys is due to formation of 😕

a. Chromium carbide

b. Ferric oxide

c. Chromium oxide

d. Cobalt oxide

38 / 60

Once amalgamation has occurred, which of the following is true of mercury ?

a. Has the toxic properties of unreacted mercury

b. Can form at the surface of amalgam restorations if heated to 0° C

c. Composite restorative resins

d. Is combined primarily with silver

39 / 60

Elgiloy arch wire is 😕

a. Gold alloy

b. Optical fiber arch wire

c. Cobalt-chromium-nickel alloy

d. β-titanium arch wire

40 / 60

Following are the functions of impression compound except 😕

a. To make individual die impression with copper band

b. To make special tray for final impression

c. To record mucostatic impressions

d. To make impression of edentulous ridge

41 / 60

Zinc oxide eugenal impression should be removed from oral cavity :

a. When it can be easily indented by a blunt instrument

b. Exactly after four minutes after kneading

c. When the material is glossy

d. When the material cannot be intended by a blunt instrument

42 / 60

Full denture bases are usually made from which of the following materials ?

a. Composite restorative resins

b. Acrylic resin

c. Gold alloys

d. Ceramic

43 / 60

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

a. Amalgam

b. Ceramic

c. Gold alloy

d. Silver alloys

44 / 60

In dental plaster the main ingredient is 😕

a. Calcium anhydrate

b. Calcium sulfate dehydrate

c. Calcium sulfate hemihydarate

d. Calcium phosphate

45 / 60

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

a. Quartz

b. Silica

c. Gypsum

d. Water

46 / 60

Potato starch is contained in which impression material ?

a. Potassium sulfate

b. Agar agar

c. Impression plaster

d. Impression compound

47 / 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. Microhybrid composites contain as much as 84% filler by weight.

d. Microfilled

48 / 60

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

a. Latent heat

b. Temperature of vaporization

c. Fusion temperature

d. Specific temperature

49 / 60

Which of the following materials are used for dental implants ?

a. Gold alloys

b. Titanium

c. Metal alloys

d. Cobalt and chromium alloys

50 / 60

The function of gum dammar in inlay wax is 😕

a. No smoothness of pattern

b. No resistance to carving

c. Less strength to wax

d. To improve smoothness of pattern

51 / 60

Gypsum investments should not be heated above 😕

a. 10000C

b. 4500C

c. 17000C

d. 7000C

52 / 60

A potentially toxic element in base metal alloys is 😕

a. Boron

b. Beryllium

c. Molybdenum

d. Magnesium

53 / 60

Nickel in base metal alloys increase its 😕

a. S Ductility

b. Modulus of elasticity

c. Strength

d. Hardness and fusion temperature

54 / 60

In alginate impression the final gel is 😕

a. Calcium alginate

b. Sodium alginate

c. Calcium sulphate

d. Sodium sulphate

55 / 60

Which of the following occurs when dental amalgam is overmixed ?

a. Compressive strength decreases

b. Corrosion increases

c. Tensile strength increases

d. Corrosion decreases

56 / 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. Artificial waxes teeth are attached

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

57 / 60

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

a. They are attached to lower natural teeth with cements,

b. They are attached to upper natural teeth with cements,

c. They are attached to natural teeth with cements,

d. Artificial acrylic teeth are attached

58 / 60

One of the following statements which one is incorrect regarding addition silicones 😕

a. No evolution of any byproduct under all circumstances

b. Dimensionally stable even after 1 week

c. Can be used in automixing devices

d. Undetectable distortion on removal

59 / 60

The main use of zinc oxide eugenol cement is 😕

a. Base

b. Permanent restoration

c. Indirect pulp capping agent

d. Temporary restoration

60 / 60

KHN of enamel is 😕

a. 90-100

b. 300

c. 600

d. 100

Your score is

The average score is 86%

Any comments?

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