Dental Materials MCQs

Option A: Gold-Copper

Option B: Nickel-Chromium

Option C: Nickel-Titanium

Option D: Silver-Palladium

Correct Answer: Gold-Copper ✔

Option A: 11.5-12.5×10-6/°C

Option B: 10.5-11.5×10-6/°C

Option C: 13.5-14.5×10-6/°C

Option D: 16.5-17.5×10-6/°C

Correct Answer: C. 13.5-14.5×10-6/°C ✔

Option A: Increase the strength

Option B: Counter balance contraction of gypsum during heating

Option C: aid in hygroscopic expansion

Option D: Increase the shelf life of investment

Correct Answer: Counter balance contraction of gypsum during heating ✔

Option A: Soft hardening treatment

Option B: Hard hardening treatment

Option C: Precipitating heat treatment

Option D: Stress relieving heat treatment

Correct Answer: Stress relieving heat treatment ✔

Option A: Hydrogen

Option B: Natural gas

Option C: Propane

Option D: Acetylene

Correct Answer: Propane ✔

Option A: Propane

Option B: Acetylene

Option C: Natural gas

Option D: Hydrogen

Correct Answer: Propane ✔

Option A: Gold solder and borax flux

Option B: Gold solder and fluoride flux

Option C: Silver Solder and borax flux

Option D: Silver solder and fluoride flux

Correct Answer: Silver solder and fluoride flux ✔

Option A: Prolonged heating:

Option B: Rapid heating me

Option C: Water film contamination

Option D: Too high pressure during casting

Correct Answer: Rapid heating me ✔

Option A: More

Option B: Less

Option C: Equal

Option D: Depends on the alloy type

Correct Answer: Less ✔

Option A: Passivity

Option B: High Fusion Temperature

Option C: High Molecular Weight

Option D: Co-efficient of Thermal Expansion

Correct Answer: Passivity ✔

Option A: Boric acid

Option B: Borax

Option C: Fluoride

Option D: Rouge

Correct Answer: Borax ✔

Option A: Greater than the substrate material

Option B: Lesser than the substrate material

Option C: Equal to the substrate material

Option D: Temperature not relevant

Correct Answer: Lesser than the substrate material ✔

Option A: Tin

Option B: Beryllium

Option C: Molybdenum

Option D: Carbon

Correct Answer: Beryllium ✔

Option A: Hydrogen

Option B: Natural gas

Option C: Acetylene

Option D: Propane

Correct Answer: Propane ✔

Option A: Magnesium oxide & Phosphate

Option B: Magnesium oxide & Phosphoric acid

Option C: Magnesium oxide & Monoammonium phosphate

Option D: Magnesium oxide & Ortho Phosphoric acid

Correct Answer: Magnesium oxide & Monoammonium phosphate ✔

Option A: Iridium

Option B: Ruthinium

Option C: Indium

Option D: Platinum

Correct Answer: ✔

Option A: Supracocclusion of restoration

Option B: Retained cement in gingival sulcus

Option C: Excess acid in mix

Option D: Galvanic current caused by gold onlay occluding with a large restoration

Correct Answer: Galvanic current caused by gold onlay occluding with a large restoration ✔

Option A: 0%

Option B: 2 to 3%

Option C: 5 to 10%

Option D: <1%

Correct Answer: 0% ✔

Option A: To felicitate wetting of ring liner

Option B: To felicitate mixing investment

Option C: To reduce contact angle of liquid with max surface

Option D: For better wax elimination

Correct Answer: To reduce contact angle of liquid with max surface ✔

Option A: Palladium

Option B: Silver

Option C: Copper

Option D: Zinc

Correct Answer: Zinc ✔

Option A: It prevents the formation of copper oxide

Option B: It prevents the formation of chromium oxide or dissolves chromic oxide layer

Option C: It prevents the flow of material in undesirable area

Option D: Increase the strength of solder

Correct Answer: It prevents the formation of chromium oxide or dissolves chromic oxide layer ✔

Option A: N 25%

Option B: 25%

Option C: >40%

Option D: 0%

Correct Answer: >40% ✔

Option A: Suckback porosity

Option B: Gas inclusion porosity

Option C: Localized shrinkage porosity

Option D: Microporosity

Correct Answer: Gas inclusion porosity ✔

Option A: Prevent the oxidation of the metal during melting

Option B: increase the melting point of the flux

Option C: Flaring the point of the sprue attachment

Option D: None of the above

Correct Answer: Flaring the point of the sprue attachment ✔

Option A: Candellila wax

Option B: Paraffin wax

Option C: Carnauba wax

Option D: Gum dammar

Correct Answer: Paraffin wax ✔

Option A: William H Taggart

Option B: Buonocore

Option C: G.V. Black

Option D: Bowen

Correct Answer: William H Taggart ✔

Option A: Rapid solidification of metal

Option B: No place for reservoirs

Option C: Incomplete evacuation of gases

Option D: Difficulty in removing casting from investment

Correct Answer: Incomplete evacuation of gases ✔

Option A: 18% Nickel 8% Chrominum

Option B: 18% Chromium 8% Nickel

Option C: 18% Chromium 8% Cobalt

Option D: 18% Carbon 8% Iron

Correct Answer: 18% Chromium 8% Nickel ✔

Option A: Temporarily cement inlays:

Option B: Make inlay wax patterns

Option C: Invest inlay patterns

Option D: Box models

Correct Answer: Make inlay wax patterns ✔

Option A: Strength

Option B: Expansion components for casting shrinkage

Option C: Decrease strength

Option D: Contraction

Correct Answer: Expansion components for casting shrinkage ✔

Option A: At right angle

Option B: At 45°C angle

Option C: At obtuse angle

Option D: It depend upon type of wax pattern

Correct Answer: At 45°C angle ✔

Option A: 25%

Option B: 50%

Option C: 75%

Option D: 100%

Correct Answer: 75% ✔

Option A: Under vacuum in argon atmosphere

Option B: Under air pressure in nitrogen atmosphere

Option C: In specially fabricated aluminium vanadium

Option D: Using CAD-CAM technique

Correct Answer: Under vacuum in argon atmosphere ✔

Option A: Heating 750°C and slowly cooling to zero degree

Option B: Heating quickly upto 450°C followed by sudden quenching

Option C: Heating upto 250°C for 15 to 30 min

Option D: Heating at 750°C and then quenching to room temperature

Correct Answer: Heating upto 250°C for 15 to 30 min ✔

Option A: Carbon crucible

Option B: Clay crucible

Option C: Quartz crucible

Option D: High melting plastic crucible

Correct Answer: Quartz crucible ✔

Option A: Quartz

Option B: Cristobalite

Option C: Tridymite

Option D: Corundum

Correct Answer: Cristobalite ✔

Option A: Cr, Al, Ti

Option B: Cr, Mo, Ti

Option C: Cr, Gold, Ti

Option D: Cr, Fe, Ti

Correct Answer: Cr, Al, Ti ✔

Option A: Primary impression

Option B: Corrective impressions

Option C: Impression of single tooth

Option D: None of the above

Correct Answer: Corrective impressions ✔

Option A: Copper cynide

Option B: Ionic copper

Option C: Acidic copper sulfate

Option D: Silver cyanide

Correct Answer: Acidic copper sulfate ✔

Option A: To strength amalgam

Option B: In orthodontic wires

Option C: To construct clasps for partial dentures

Option D: To replace internal gold restorations

Correct Answer: In orthodontic wires ✔

Option A: Animal

Option B: Mineral

Option C: Insect

Option D: Vegetable

Correct Answer: Animal ✔

Option A: Utility wax

Option B: Base plate wax

Option C: Beading wax

Option D: Boxing wax

Correct Answer: Utility wax ✔

Option A: Pinhole porosity

Option B: Gas inclusion porosity

Option C: Micro porosity

Option D: Subsurface porosity

Correct Answer: Subsurface porosity ✔

Option A: To provide a smooth and glossy surface

Option B: Increase toughness

Option C: Decrease toughness

Option D: Decrease flow at room temperature

Correct Answer: Decrease flow at room temperature ✔

Option A: Platinum

Option B: Copper

Option C: Silver

Option D: Gold

Correct Answer: Copper ✔

Option A: Tensile strength

Option B: Proportional limit

Option C: Ductility

Option D: Hardness

Correct Answer: Ductility ✔

Option A: Form an opening of molten metal to enter the mold

Option B: Help polish cast restorations

Option C: Eliminate air bubbles on the wax pattern

Option D: Reproduce fine detail

Correct Answer: Form an opening of molten metal to enter the mold ✔

Option A: Carbon

Option B: Chromium

Option C: Nickel

Option D: Titanium

Correct Answer: Titanium ✔

Option A: 100 Mpa

Option B: 240 Mpa

Option C: 560 Mpa

Option D: 700 Mpa

Correct Answer: 560 Mpa ✔

Option A: Dimensional change

Option B: Thermal conductivity

Option C: Warpage

Option D: Tarnish and corrosion

Correct Answer: Tarnish and corrosion ✔

Option A: Impurities in gold

Option B: Improper venting

Option C: A and B

Option D: None of the above

Correct Answer: None of the above ✔

Option A: High gold

Option B: Low gold

Option C: Palladium – Ag

Option D: Ni – Cr

Correct Answer: D. Ni – Cr ✔

Option A: Improve bonding

Option B: Harden the metal ceramic Ag-Pd alloy

Option C: Both A and B

Option D: None of the above

Correct Answer: Both A and B ✔

Option A: Iowa wax

Option B: Modeling wax

Option C: Green stick wax

Option D: None of the above

Correct Answer: Iowa wax ✔

Option A: More porous investment in the mould

Option B: Narrow sprue diameter

Option C: Hollow sprue pin

Option D: Large reservoir

Correct Answer: Narrow sprue diameter ✔

Option A: Shrinkage of alloy on cooling

Option B: Investment breakdown

Option C: Incomplete wax elimination

Option D: Incomplete gas elimination

Correct Answer: Incomplete wax elimination ✔

Option A: 700°C

Option B: 1,300°C

Option C: 1,063°C

Option D: 900°C

Correct Answer: 700°C ✔

Option A: 30% cobalt and 60% chrominum

Option B: 60% cobalt and 30% chrominum

Option C: 1% palladium

Option D: 20% gold

Correct Answer: 60% cobalt and 30% chrominum ✔

Option A: Ti 6Al 4V

Option B: Ti 5Al 4V

Option C: Ti 5Al 5V

Option D: Ti 6Al 6V

Correct Answer: Ti 6Al 4V ✔

Option A: Decrease flow

Option B: Continuous expansion

Option C: Relaxation of the internal stresses

Option D: Water loss

Correct Answer: Relaxation of the internal stresses ✔

Option A: 19%

Option B: 2%

Option C: 1.7%

Option D: 4%

Correct Answer: 1.7% ✔

Option A: Remove the oxides formed on the gold alloy

Option B: Lower the melting point

Option C: Replace casting wax

Option D: Speed the burnout process

Correct Answer: Remove the oxides formed on the gold alloy ✔

Option A: High quality iron

Option B: Chrome

Option C: Cobalt

Option D: Nickel

Correct Answer: Chrome ✔

Option A: Ease of construction of denture

Option B: Preserving the sulci

Option C: Ease of pouring an impression

Option D: All of the above

Correct Answer: Ease of pouring an impression ✔

Option A: ¼ inch

Option B: ½ inch

Option C: 3/8 inch

Option D: one inch

Correct Answer: ¼ inch ✔

Option A: Decrease its strength and ability to be hardened

Option B: Decrease its tarnish resistance

Option C: Increase its fusion temperature

Option D: Redden the alloy

Correct Answer: Increase its fusion temperature ✔

Option A: They have a modulus of elasticity twice that of gold alloys

Option B: They are more rigid than gold alloys

Option C: They have higher ductility than gold alloys

Option D: They have a lower proportional limit than gold alloys

Correct Answer: They have higher ductility than gold alloys ✔

Option A: Solid

Option B: Liquid

Option C: Gas

Option D: Colloid

Correct Answer: Colloid ✔

Option A: It should be rapidly displaced from the mouth

Option B: It may exhibit fluid exudates on the surface as a result of imbibition of water

Option C: It will take up water and expand if kept wet

Option D: It will shrink as a result of syneresis

Correct Answer: It may exhibit fluid exudates on the surface as a result of imbibition of water ✔

Option A: Their use

Option B: Their hardness after setting

Option C: Water content

Option D: Eugenol content

Correct Answer: Their hardness after setting ✔

Option A: Imbibition

Option B: Syneresis

Option C: Hysteresis

Option D: Gelation

Correct Answer: Imbibition ✔

Option A: Addition poly silicone

Option B: Agar-agar

Option C: Polysulphide

Option D: Polyether

Correct Answer: Addition poly silicone ✔

Option A: Act as a scavenger

Option B: Helps as surfactant

Option C: Acts as plasticizer

Option D: Acts as a catalyst

Correct Answer: Act as a scavenger ✔

Option A: Condensation polysillicon

Option B: Addition Polysilicon

Option C: Polyether

Option D: A and B

Correct Answer: Condensation polysillicon ✔

Option A: High viscosity elastomeric impression material

Option B: Medium viscosity elastomeric impression material

Option C: Low viscosity elastomeric impression material

Option D: None of the above

Correct Answer: Low viscosity elastomeric impression material ✔

Option A: Non-elastic impression material

Option B: Thermoplastic impression material

Option C: More mucostatic than ZOE

Option D: Less mucostatic than ZOE

Correct Answer: Less mucostatic than ZOE ✔

Option A: High viscosity elastomer

Option B: Medium viscosity elastomer

Option C: Medium & low viscosity elastomer

Option D: Low viscosity elastomer

Correct Answer: Low viscosity elastomer ✔

Option A: Impression wax

Option B: Modelling compound

Option C: Hydro-colloid

Option D: Hydro cal

Correct Answer: Hydro-colloid ✔

Option A: Mechanical action of saliva

Option B: Physical change

Option C: Evolution

Option D: Chemical change

Correct Answer: Physical change ✔

Option A: Irreversible hydrocolloid

Option B: Reversible hydrocolloid

Option C: Impression plaster

Option D: Metallic oxide paste

Correct Answer: Reversible hydrocolloid ✔

Option A: Raising the temperature of water used for maxing

Option B: Using excess water for maxing

Option C: Lowering the temperature of water used for mixing

Option D: None of the above

Correct Answer: Raising the temperature of water used for maxing ✔

Option A: Continue to polymerize

Option B: Become elastic

Option C: Show imbibition and syneresis

Option D: Show gelation

Correct Answer: Continue to polymerize ✔

Option A: Thin mix of plaster of paris

Option B: Zinc oxide eugenol impression paste

Option C: Free flowing wax

Option D: Reversible hydrocolloids

Correct Answer: Thin mix of plaster of paris ✔

Option A: Slight rocking of the impression to disengage it from the undercut

Option B: Wetting the periphery of the impression with moist cotton to break the peripheral seal

Option C: Sudden jerking of the impression to prevent tearing

Option D: Supporting the impression along with the tray to prevent disengaging of the tray alone

Correct Answer: Sudden jerking of the impression to prevent tearing ✔

Option A: Silicone

Option B: Agar-agar

Option C: Impression paste

Option D: Impression plaster

Correct Answer: Agar-agar ✔

Option A: Decrease flow

Option B: Increase flow

Option C: Accelerate reaction

Option D: Decrease irritation due to eugenol

Correct Answer: Increase flow ✔

Option A: Bullock heart

Option B: Chemicals

Option C: Sea weed

Option D: Chick cells

Correct Answer: Sea weed ✔

Option A: Alginate

Option B: Zinc oxide-eugenol

Option C: Agar-agar

Option D: Impression compound

Correct Answer: Alginate ✔

Option A: Trisodium phosphate reacts with sodium alginate

Option B: Trisodium phosphate reacts with calcium sulphate

Option C: Colloidal changes to sol

Option D: Material in contact with soft tissues sets last

Correct Answer: Trisodium phosphate reacts with calcium sulphate ✔

Option A: Accelerating the setting stage of gypsum

Option B: Increase strength

Option C: Give dimensional stability

Option D: None of the above

Correct Answer: Accelerating the setting stage of gypsum ✔

Option A: Impression plaster

Option B: Impression paste

Option C: Alginate

Option D: Rubber base impression material

Correct Answer: Impression paste ✔

Option A: polyether polymer

Option B: Colloidal silica

Option C: Glycol ether

Option D: Di-vinyl poly (dimethyl siloxane)

Correct Answer: Glycol ether ✔

Option A: Concentration of filler and plasticizer

Option B: Percentage composition by weight of water

Option C: Concentration of potassium sulphate

Option D: Temperature

Correct Answer: Temperature ✔

Option A: Sol

Option B: Gel

Option C: Hydrocolloid

Option D: Colloid

Correct Answer: Hydrocolloid ✔

Option A: Hydrocolloids

Option B: Elastomers

Option C: Zinc oxide eugenol

Option D: Plaster of paris

Correct Answer: Hydrocolloids ✔

Option A: Has dimensional stability

Option B: Does not adhere to tissues

Option C: Is easy manipulation

Option D: Does not require special trays

Correct Answer: Has dimensional stability ✔

Option A: Remove excess impression material

Option B: Remove saliva

Option C: Hydrate the impression

Option D: Accelerate the setting

Correct Answer: Remove saliva ✔

Option A: Impression plaster

Option B: Irreversible hydrocolloid

Option C: Reversible hydroollioid

Option D: None of the above

Correct Answer: Irreversible hydrocolloid ✔

Option A: Impression plaster

Option B: Impression paste

Option C: Silicon impression material

Option D: None of the above

Correct Answer: None of the above ✔

Option A: CaCl2

Option B: Zinc acetate

Option C: Alcohol

Option D: Glycerine

Correct Answer: Glycerine ✔