VJ Pratab Dental Materials
Dental Materials
1: The limited shelf-life of condensation silicones is usually the result of deterioration of which of the
following components ?
1: Lithopone
2: Tin component
3: Diurethyl siloxane
4: Platinum salt
Ans: 2
2: The restorative resins currently most popular are the
1: unfilled direct filling, light-curing resins
2: filled polyurethane resins
3: acrylic resins
4: microfilled composite resins
Ans: 4
3: The decrease in the marginal leakage of an amalgam restoration is primarily the result of
1: using cavity varnish
2: water sorption
3: expansion of the alloy
4: formation of corrosion products
Ans: 4
4: The pH of zinc phosphate cement be-comes neutral in
1: 30-60 minutes
2: 24-48 hours
3: 1 week
4: 4-6 hours
Ans:2
5: Which metals expand on from the molten state?
1: Platinum and palladium
2: Iridium and lead
3: Indium and strontium
FCPS Part 1 Dentistry
4: Bismuth and antimony
5: None of the above
Ans: 4
6: Sprues can be fabricated from all of the following, except
1: wax
2: resin
3: stainless steel
4: plastic
5: none of the above
Ans: 5
7: Wrought gold alloys are used in dentistry primarily as
1: full crowns
2: inlays
,3: wires
4: arch bars
5: metal ceramics
Ans: 3
8: A Type IV partial denture gold alloy exceeds a base-metal alloy in numerical value in
1: compressive strength
2: casting shrinkage
3: hardness
4: specific gravity
5: modulus of elasticity
Ans: 4
9: Heating a gypsum investment to 1000°C will result in the liberation of
1: silver sulfide
2: carbon monoxide
3: hydrogen
4: sulfur dioxide
Ans: 4
10: Crystallinity of a polymer will result in an increase in its
FCPS Part 1 Dentistry
1: molding temperature
2: solubility
3: ductility
4: none of the above
Ans: 1
11: coupling agents in composite resins act to
1: increase cross-linking
2: bind the matrix together
3: bind the filler together
4: bind the filler to the matrix
Ans: 4
12: The mercury content of the finished amalgam restoration should be approximately
1: 40%
2: 50%
3: 60%
4: less than 35%
Ans: 2
13: The lost wax technique was first described in
1: 1907 by Taggart
2: 1930 by Skinner
3: 1898 by Hollenback
4: 1765 by jelenko
Ans: 1
14: Which of the following properties would be of least importance, when selecting an impression
material?
1: Dimensional stability
2: Biocompatibility
3: Flow
,4: Adhesion
5: Ease of manipulation
Ans:4
15: The polymer: monomer ratio for heat-cured acrylic resin
FCPS Part 1 Dentistry
1: is about 1 to 3 by volume
2: if too high will result in granularity of the acrylic
3: if too high will result in excessive shrinkage
4: if too high will have a longer reaction time
Ans: 2
16: Which portion of the set silicate resto-ration disintegrates first in oral fluids?
1: Calcium fluoride flux
2: Gel matrix
3: Silicon dioxide particles
4: Zn3(PO4)2 buffer
5: All portions disintegrate together
Ans: 2
17: Copper and silver in dental amalgam
1: increase compressive strength and expansion
2: aid in amalgamation and decrease expansion
3: reduce hardness and expansion only
4: decrease hardness, flow, expansion and compressive strength
Ans: 1
18: When epoxy resins are used for die fabrication, the resultant die will
1: be slightly undersize
2: not burn out in the furnace
3: have poor abrasion resistance
4: have low strength
5: all of the above
Ans: 1
19: Which of the following cannot result in surface roughness or irregularities of gold castings?
1: Under heating the mold
2: Heating the alloy to too high a temperature
3: Employing too high casting pressures
4: Prolonged heating of the mold
5: None of the above
Ans: 5
20: Silicate cement powders are made up of oxides or fluorides of all of the following, except
FCPS Part 1 Dentistry
1: aluminium
2: tin
3: calcium
4: sodium
5: silicon
Ans: 2
21. Sodium N-lauroyl sarcosinate is used in dentifrice pastes as a
, 1. detergent
2. humectant
3. therapeutic agent
4. Binder
Ans: 1
22: During the casting of noble metal alloys, the mold should be held at the burn out temperature for
at
least
1. 15 minutes
2. 60 minutes
3. 3 hours
4. 6 hours
Ans: 2
23: In general the hygroscopic expansion of gypsum investments will be higher if they contain
1: coarser silica particles and alpha hemihydrate
2. liner silica particles and beta hemi hydrate
3. coarser silica particles and beta hemihydrates
4. finer silica particles and alpha hemihydrate
Ans: 4
24: The cement capable of forming a chemical bond with tooth structure is
I: reinforced zinc oxide eugenol cement.
2. silicophosphate cement
3. polycarboxylate cement
4 composite resin cement
Ans: 3
25: Quartz in dental porcelain acts as a
1. binder
2. frit
3. opacifier
4. Strengthener
Ans: 4
26: The principal strengthening phaseof Cerestore, an injection molded ceramic material, are
1. aluminium oxide and silicon oxide
2. magnesium silicate and beta-aluminium
3. alpha-alumina and magnesium aluminate Spinel
4. none of the above
Ans: 3
27: Which of the following resins may be classified as thermosetting?
1. Polystyrenes
2. Vinyl resins
3. Epoxy resins
4. Impression compound
5 None of the above
Ans: 3
28: A dental appliance containing metals or soft lining materials, should not be cleaned with denture
cleansers containing
Dental Materials
1: The limited shelf-life of condensation silicones is usually the result of deterioration of which of the
following components ?
1: Lithopone
2: Tin component
3: Diurethyl siloxane
4: Platinum salt
Ans: 2
2: The restorative resins currently most popular are the
1: unfilled direct filling, light-curing resins
2: filled polyurethane resins
3: acrylic resins
4: microfilled composite resins
Ans: 4
3: The decrease in the marginal leakage of an amalgam restoration is primarily the result of
1: using cavity varnish
2: water sorption
3: expansion of the alloy
4: formation of corrosion products
Ans: 4
4: The pH of zinc phosphate cement be-comes neutral in
1: 30-60 minutes
2: 24-48 hours
3: 1 week
4: 4-6 hours
Ans:2
5: Which metals expand on from the molten state?
1: Platinum and palladium
2: Iridium and lead
3: Indium and strontium
FCPS Part 1 Dentistry
4: Bismuth and antimony
5: None of the above
Ans: 4
6: Sprues can be fabricated from all of the following, except
1: wax
2: resin
3: stainless steel
4: plastic
5: none of the above
Ans: 5
7: Wrought gold alloys are used in dentistry primarily as
1: full crowns
2: inlays
,3: wires
4: arch bars
5: metal ceramics
Ans: 3
8: A Type IV partial denture gold alloy exceeds a base-metal alloy in numerical value in
1: compressive strength
2: casting shrinkage
3: hardness
4: specific gravity
5: modulus of elasticity
Ans: 4
9: Heating a gypsum investment to 1000°C will result in the liberation of
1: silver sulfide
2: carbon monoxide
3: hydrogen
4: sulfur dioxide
Ans: 4
10: Crystallinity of a polymer will result in an increase in its
FCPS Part 1 Dentistry
1: molding temperature
2: solubility
3: ductility
4: none of the above
Ans: 1
11: coupling agents in composite resins act to
1: increase cross-linking
2: bind the matrix together
3: bind the filler together
4: bind the filler to the matrix
Ans: 4
12: The mercury content of the finished amalgam restoration should be approximately
1: 40%
2: 50%
3: 60%
4: less than 35%
Ans: 2
13: The lost wax technique was first described in
1: 1907 by Taggart
2: 1930 by Skinner
3: 1898 by Hollenback
4: 1765 by jelenko
Ans: 1
14: Which of the following properties would be of least importance, when selecting an impression
material?
1: Dimensional stability
2: Biocompatibility
3: Flow
,4: Adhesion
5: Ease of manipulation
Ans:4
15: The polymer: monomer ratio for heat-cured acrylic resin
FCPS Part 1 Dentistry
1: is about 1 to 3 by volume
2: if too high will result in granularity of the acrylic
3: if too high will result in excessive shrinkage
4: if too high will have a longer reaction time
Ans: 2
16: Which portion of the set silicate resto-ration disintegrates first in oral fluids?
1: Calcium fluoride flux
2: Gel matrix
3: Silicon dioxide particles
4: Zn3(PO4)2 buffer
5: All portions disintegrate together
Ans: 2
17: Copper and silver in dental amalgam
1: increase compressive strength and expansion
2: aid in amalgamation and decrease expansion
3: reduce hardness and expansion only
4: decrease hardness, flow, expansion and compressive strength
Ans: 1
18: When epoxy resins are used for die fabrication, the resultant die will
1: be slightly undersize
2: not burn out in the furnace
3: have poor abrasion resistance
4: have low strength
5: all of the above
Ans: 1
19: Which of the following cannot result in surface roughness or irregularities of gold castings?
1: Under heating the mold
2: Heating the alloy to too high a temperature
3: Employing too high casting pressures
4: Prolonged heating of the mold
5: None of the above
Ans: 5
20: Silicate cement powders are made up of oxides or fluorides of all of the following, except
FCPS Part 1 Dentistry
1: aluminium
2: tin
3: calcium
4: sodium
5: silicon
Ans: 2
21. Sodium N-lauroyl sarcosinate is used in dentifrice pastes as a
, 1. detergent
2. humectant
3. therapeutic agent
4. Binder
Ans: 1
22: During the casting of noble metal alloys, the mold should be held at the burn out temperature for
at
least
1. 15 minutes
2. 60 minutes
3. 3 hours
4. 6 hours
Ans: 2
23: In general the hygroscopic expansion of gypsum investments will be higher if they contain
1: coarser silica particles and alpha hemihydrate
2. liner silica particles and beta hemi hydrate
3. coarser silica particles and beta hemihydrates
4. finer silica particles and alpha hemihydrate
Ans: 4
24: The cement capable of forming a chemical bond with tooth structure is
I: reinforced zinc oxide eugenol cement.
2. silicophosphate cement
3. polycarboxylate cement
4 composite resin cement
Ans: 3
25: Quartz in dental porcelain acts as a
1. binder
2. frit
3. opacifier
4. Strengthener
Ans: 4
26: The principal strengthening phaseof Cerestore, an injection molded ceramic material, are
1. aluminium oxide and silicon oxide
2. magnesium silicate and beta-aluminium
3. alpha-alumina and magnesium aluminate Spinel
4. none of the above
Ans: 3
27: Which of the following resins may be classified as thermosetting?
1. Polystyrenes
2. Vinyl resins
3. Epoxy resins
4. Impression compound
5 None of the above
Ans: 3
28: A dental appliance containing metals or soft lining materials, should not be cleaned with denture
cleansers containing
