Metallurgy MCQs

Option A: Type I and Type II gold can be heat treated and annealed

Option B: Type III and Type IV gold can be heat treated and annealed

Option C: Type I and IV gold can be heat treated and annealed

Option D: All the type of gold can be heat treated and annealed

Correct Answer: Type III and Type IV gold can be heat treated and annealed ✔

Option A: Casts

Option B: Models

Option C: Investment

Option D: Dies

Correct Answer: Investment ✔

Option A: Using asbestos linear

Option B: Placing the sprue at least one quarter inch away form the end of casting ring

Option C: Preventing rapid heating the investment in burnout oven

Option D: Using a short and wide sprue

Correct Answer: Placing the sprue at least one quarter inch away form the end of casting ring ✔

Option A: Reducing flame

Option B: Oxidizing flame

Option C: Green flame

Option D: All of the above

Correct Answer: Reducing flame ✔

Option A: Warm HCI

Option B: Cold HF

Option C: Cold H2SO4

Option D: Sand blasting with aluminium oxide

Correct Answer: Sand blasting with aluminium oxide ✔

Option A: a titanium

Option B: B titanium

Option C: Chrome-cobalt-nickel

Option D: Nickel-titanium

Correct Answer: Nickel-titanium ✔

Option A: Produce a smoother casting

Option B: Decrease setting expansion

Option C: Increase setting expansion

Option D: Increase thermal expansion

Correct Answer: Decrease setting expansion ✔

Option A: Tempering

Option B: Work hardening

Option C: Age hardening

Option D: Precipitation hardening

Correct Answer: Work hardening ✔

Option A: Is accomplished by soaking the casting in baking soda

Option B: Causes porosity in gold

Option C: Removes surface oxides from gold castings

Option D: Remove investment from gold casting

Correct Answer: Removes surface oxides from gold castings ✔

Option A: Shape memory

Option B: Hyper rigidity

Option C: Corrosion resistance

Option D: Weldable properties

Correct Answer: Shape memory ✔

Option A: Martensite

Option B: Ferrite

Option C: Austenite

Option D: Pearlite

Correct Answer: Austenite ✔

Option A: Carbon content

Option B: Silica content

Option C: Gypsum

Option D: Copper

Correct Answer: Gypsum ✔

Option A: Low fusing ceramic and high fusing alloys

Option B: Matching of coefficients of thermal expansion of ceramics and alloy

Option C: Bonding between ceramic and alloy

Option D: All of the above

Correct Answer: All of the above ✔

Option A: Inlay wax type-II

Option B: Boxing wax

Option C: Modelling wax

Option D: Casting wax

Correct Answer: Casting wax ✔

Option A: 0.4%

Option B: 1.4%

Option C: 2.4%

Option D: 3.4%

Correct Answer: 1.4% ✔

Option A: Increases its toughness

Option B: Increases hardness

Option C: Increase ductility

Option D: decreases its toughness

Correct Answer: Increase ductility ✔

Option A: Wrought alloy

Option B: Palladium alloys

Option C: Cobalt-chrome alloys

Option D: Partial denture casting gold in hardened condition

Correct Answer: Cobalt-chrome alloys ✔

Option A: Molybdenum

Option B: Germanium

Option C: Titanium

Option D: Chromium

Correct Answer: Titanium ✔

Option A: Alpha form

Option B: Beta form

Option C: Gamma form

Option D: None of the above

Correct Answer: Gamma form ✔

Option A: Oxidizing zone

Option B: Reducing zone

Option C: Combustion zone

Option D: None of the above

Correct Answer: Oxidizing zone ✔

Option A: Thin sprue

Option B: No reservoir

Option C: Investment heated strongly

Option D: Inadequate air discharge

Correct Answer: Thin sprue ✔

Option A: Decreasing the sprue length

Option B: Decreasing the sprue thickness

Option C: Increasing the melting temperature

Option D: Increasing the mould temperature

Correct Answer: Decreasing the sprue thickness ✔

Option A: Type 1

Option B: Type 2

Option C: Type 3

Option D: Type 4

Correct Answer: Type 1 ✔

Option A: Carats

Option B: Percentage

Option C: Fineness

Option D: Gram

Correct Answer: Fineness ✔

Option A: Improve bonding

Option B: Decrease porosity

Option C: They react with the porcelain opaque layer, which masks the metal

Option D: Improves the thermal expansion between the metal and porcelain

Correct Answer: Improve bonding ✔

Option A: Gypsum bonded

Option B: Phosphate bonded

Option C: Silica bonded

Option D: None of the above

Correct Answer: Phosphate bonded ✔

Option A: Is applied to the walls of the investment to produce hygroscopic expansion

Option B: Increase the strength and the setting expansion of the phosphate-bonded investment

Option C: Acts as a retarder in the silica bonded investments

Option D: Acts as a refractory in the Silica bonded investments

Correct Answer: Increase the strength and the setting expansion of the phosphate-bonded investment ✔

Option A: Carding wax

Option B: Inlay wax

Option C: Utility wax

Option D: Sticky wax

Correct Answer: Carding wax ✔

Option A: Austenite to martensite

Option B: Martensite to austenite

Option C: Ferrite to austenite

Option D: Austenite to ferrite

Correct Answer: Austenite to martensite ✔

Option A: Thermal expansion

Option B: Hygroscopic expansion

Option C: Wax expansion

Option D: All of the above

Correct Answer: All of the above ✔

Option A: 55

Option B: 65

Option C: 75

Option D: 85

Correct Answer: 75 ✔

Option A: Annealing

Option B: Degassing

Option C: Pickling

Option D: Conditioning

Correct Answer: Pickling ✔

Option A: Stainless steel wire

Option B: NITTINOL wire

Option C: TMA wire

Option D: Aluminium

Correct Answer: NITTINOL wire ✔

Option A: Hydrochloric acid

Option B: Nitric acid

Option C: Sulphuric acid

Option D: Phosphoric acid

Correct Answer: Hydrochloric acid ✔

Option A: Chromium carbide

Option B: Carbon carbide

Option C: Iron carbide

Option D: Nickel carbide

Correct Answer: Chromium carbide ✔

Option A: Recovery stage

Option B: Recrystallisation stage

Option C: Grain growth stage

Option D: All of the above

Correct Answer: Recrystallisation stage ✔

Option A: Unfilled acrylic plastics

Option B: Gold alloys

Option C: Porcelains

Option D: Zinc phosphate cements

Correct Answer: Gold alloys ✔

Option A: Platinium

Option B: Palladium

Option C: Titanium

Option D: Gold

Correct Answer: Titanium ✔

Option A: Paraffin wax

Option B: Inlay wax

Option C: Microcrystalline wax

Option D: Montan wax

Correct Answer: Montan wax ✔

Option A: Silver fluorides

Option B: Silver cyanide

Option C: Silver bromide

Option D: Silver iodide

Correct Answer: Silver cyanide ✔

Option A: Attached impurities on undersurface of casting

Option B: Hot spot

Option C: No rapid cooling

Option D: Inadequate melting temperature

Correct Answer: Hot spot ✔

Option A: Improper casting pressure

Option B: Improper heating of the investment

Option C: Improper angulation of sprue

Option D: Improper wetting of the wax pattern by the investment

Correct Answer: Improper wetting of the wax pattern by the investment ✔

Option A: Facilitate venting of the mold

Option B: Retard the heating of the investment

Option C: Permit expansion of the world

Option D: All of the above

Correct Answer: Permit expansion of the world ✔

Option A: Surface hardness

Option B: Strength

Option C: Proportion limit

Option D: Corrosion resistance

Correct Answer: Corrosion resistance ✔

Option A: Increasing the mould metal temperature difference

Option B: Increasing the flow of molten metal

Option C: Flaring the point of the sprue attachment

Option D: All of the above

Correct Answer: Flaring the point of the sprue attachment ✔

Option A: Carbon

Option B: Molybdenum

Option C: Chromium

Option D: Nickel

Correct Answer: Carbon ✔

Option A: Silica

Option B: Quartz

Option C: Cristobolite

Option D: Calcium sulphate monohydrate

Correct Answer: Calcium sulphate monohydrate ✔

Option A: Unreliable spring back

Option B: low spring back

Option C: Minimal spring back

Option D: None of the above

Correct Answer: None of the above ✔

Option A: Low weight

Option B: Low cost

Option C: Low strength

Option D: Low melting point

Correct Answer: Low weight ✔

Option A: Paraffin

Option B: Carnauba

Option C: Gum dammar

Option D: Canadelila

Correct Answer: Gum dammar ✔

Option A: Fibrous

Option B: Homogeneous

Option C: Inhomogenous

Option D: amorphous

Correct Answer: Inhomogenous ✔

Option A: Constitutional superconductivity

Option B: Constitutional supercooling

Option C: Constitutional supergriting

Option D: Constitutional supergraining

Correct Answer: Constitutional supercooling ✔

Option A: Increased hardness

Option B: Increased ductility

Option C: Better biocompatibility

Option D: Increased density

Correct Answer: Increased hardness ✔

Option A: Type III and Type IV gold

Option B: Type V and type VI gold

Option C: Type VII and type VIII gold

Option D: None of the above

Correct Answer: Type III and Type IV gold ✔

Option A: Age hardening heat treatment

Option B: Annealing heat treatment

Option C: Homogenization heat treatment

Option D: Solution heat treatment

Correct Answer: Annealing heat treatment ✔

Option A: Back pressure porosity

Option B: Localized shrinkage porosity

Option C: Pin hole porosity

Option D: Micro porosity

Correct Answer: Localized shrinkage porosity ✔

Option A: 2.3%

Option B: 1.56%

Option C: 1.37%

Option D: 3%

Correct Answer: 2.3% ✔

Option A: Type I – Soft

Option B: Type II – Hard

Option C: Type III – Hard

Option D: Type IV – Extra Hard

Correct Answer: D. Type IV – Extra Hard ✔

Option A: Chromium

Option B: Indium

Option C: Irridium

Option D: Palladium

Correct Answer: Irridium ✔

Option A: Strengtherner

Option B: Hardener

Option C: Whitens the alloy

Option D: Scavenger

Correct Answer: Strengtherner ✔

Option A: Recovery recrystallization grain growth

Option B: Recrystallization recovery, grain growth

Option C: Grain Growth Recrystallization recovery

Option D: Melting point, grain growth, Recrystallization

Correct Answer: Recovery recrystallization grain growth ✔

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 ✔