8651. Impression material that Do NOT harden by chemical reaction_______________?
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A. Plaster of paris

B. Impression compound

C. Alginate

D. Zinc oxide eugenol

8652. 18-B Stainless steel orthodontic wire has_______________?
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A. 18% Chromium 8% Cobalt

B. 18% Chromium 8% Nickel

C. 18% Nickel 8% Chrominum

D. 18% Carbon 8% Iron

8653. Casting shrinkage is compensated by_______________?
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A. Hygroscopic expansion

B. Thermal expansion

C. All of the above

D. Wax expansion

8654. Which of the following impression material is elastic________________?
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A. Impression compound

B. Polyvinyl siloxane

C. Zinc Oxide eugenol (ZOE) paste

D. Wax

8656. Trisodium phosphate in alginate acts are_______________?
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A. Plasticizer

B. Reactor

C. Accelerator

D. Retarder
8657. The term ordered hardening heat treatment used in which of the following dental alloys ?
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A. Silver-Palladium

B. Nickel-Titanium

C. Nickel-Chromium

D. Gold-Copper
8658. One of the most important advantages of truly elastic impression material would be its capacity for______________?
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A. With drawl without permanent distortion

B. Close adaptation to soft tissues

C. Reproduction of surface details

D. Compatibility with gypsum products

8659. Accelerators and retarders are used with gypsum products mainly to control_______________?
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A. Hardness of the set product

B. Setting expansion

C. None of the above

D. Setting time
8660. Heat hardening is the process done at_______________?
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A. Heating at 750C and then quenching to room temperature

B. Heating 750C and slowly cooling to zero degree

C. Heating quickly upto 450C followed by sudden quenching

D. Heating upto 250C for 15 to 30 min
8661. Shape memory is seen in________________?
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A. Aluminium

B. NITTINOL wire

C. Stainless steel wire

D. TMA wire

8663. In plaster of paris the setting time is primarily altered by_________________?
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A. Speed and length of hand spatulation

B. Altering P / L Ratio

C. Altering temperature of mixing water

D. Addition of accelerators and retarders
8665. A rough / Chalky surface of the cast is due to_______________?
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A. Not waiting for 20 min before pouring

B. Air incorporation in the mix

C. All of the above

D. High speed accelerator

8666. Heavy and light body impression materials are use with______________?
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A. Reversible hydrocolloid

B. Silicone

C. A and B

D. Mercaptan

8669. Balanced stone is dental stone_______________?
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A. In which accelerators or retarders have been added according to need

B. In which the crystals are all of uniform size

C. Which undergoes rapid expansion

D. In which amount of water of hydration is controlled

8671. Air bubbles formed on the surface of casting is probably due to________________?
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A. Improper casting pressure

B. Improper heating of the investment

C. Improper angulation of sprue

D. Improper wetting of the wax pattern by the investment
8672. Which of the waxes are derived from the lignite_________________?
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A. Inlay wax

B. Montan wax

C. Paraffin wax

D. Microcrystalline wax

8673. Casting flux is used to_______________?
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A. increase the melting point of the flux

B. Flaring the point of the sprue attachment

C. None of the above

D. Prevent the oxidation of the metal during melting

8674. The plasticizers used in polyether impression material is_______________?
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A. polyether polymer

B. Colloidal silica

C. Glycol ether

D. Di-vinyl poly (dimethyl siloxane)

8676. Mechanical properties of Cp Titanium are similar to alloys_____________?
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A. Type VII and type VIII gold

B. None of the above

C. Type III and Type IV gold

D. Type V and type VI gold

8678. Retarder in Zinc oxide eugenol is______________?
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A. Alcohol

B. CaCl2

C. Zinc acetate

D. Glycerine
8679. A laminate impression technique utilizes_______________?
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A. Syringe agar and tray agar

B. Syringe agar and chilled tray alginate

C. Syringe agar and impression compound

D. Chilled alginate and impression compound

8680. Passivating alloys are_______________?
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A. Cr, Gold, Ti

B. Cr, Fe, Ti

C. Cr, Al, Ti

D. Cr, Mo, Ti

8681. Nickel is added to wrought gold alloys as______________?
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A. Strengtherner

B. Whitens the alloy

C. Scavenger

D. Hardener

8682. Die is________________?
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A. Replica of single tooth

B. Impression of whole teeth

C. Replica of whole teeth

D. Impression of single tooth

8683. Agar is prepared from_______________________?
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A. Chick cells

B. Chemicals

C. Bullock heart

D. Sea weed
8684. During soldering, the solidus temperature of the filler material should be_____________?
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A. Equal to the substrate material

B. Temperature not relevant

C. Lesser than the substrate material

D. Greater than the substrate material

8685. Alginate impression material is similar to Agar-agar impression material in the following respect________________?
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A. Gelation increase in both on increase in temperature

B. Mixing time is increased to reduce the setting time

C. Deformation during removal of impression occurs due to distortion of gel fibers

D. Both can be re-used for fresh impressions

8686. Quartz is added to gypsum bonded investment to______________?
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A. Increase the shelf life of investment

B. aid in hygroscopic expansion

C. Increase the strength

D. Counter balance contraction of gypsum during heating
8687. The cross linking agent of polysulphide rubber base impression material is______________?
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A. Platinum salt catalyst

B. Lead dioxide

C. Stannous octate

D. Aromatic sulfonate esters

8688. Beta hemihydrate particles absorb______________?
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A. no water

B. Less water

C. None of the above

D. More water
8689. Hardening solutions are used with impression made of________________?
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A. Impression compound

B. Elastomer

C. Hydrocolloid

D. Zinc oxide eugenol

8690. Rinsing of the impression is important to________________?
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A. Remove saliva

B. Remove excess impression material

C. Accelerate the setting

D. Hydrate the impression

8691. Asbestos liner is used in a casting ring to________________?
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A. Permit expansion of the world

B. Retard the heating of the investment

C. All of the above

D. Facilitate venting of the mold

8692. Syneresis is associated with______________?
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A. Zinc oxide eugenol

B. Plaster of paris

C. Hydrocolloids

D. Elastomers

8693. Which is gypsum product_______________?
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A. All of the above

B. Investment

C. Plaster

D. Stone

8695. Type I gypsum product is also called_______________?
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A. Class I stone / Hydrocal

B. Class II stone/Densite

C. Impression plaster

D. Model plaster

8696. Annealing is also known as_______________?
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A. Soft hardening treatment

B. Hard hardening treatment

C. Precipitating heat treatment

D. Stress relieving heat treatment
8697. Palladium is added to polyvinyl siloxane to_____________?
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A. Acts as plasticizer

B. Helps as surfactant

C. Act as a scavenger

D. Acts as a catalyst

8698. Which of the following is not true about elastomeric impression ?
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A. Putty wash technique of impression reduces dimensional change of setting

B. Shear thinning is related to viscosity of non phase impression material

C. Single mix material have higher viscosity

D. Improper mixing of material can cause permanent deformation of impression

8700. Putty wash technique_________________?
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A. None of the above

B. Light body and putty used at the same time

C. Light body first and putty later

D. Putty used first and light body used second