Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

dentmat > dent > Flashcards

dent Flashcards

1
Q

On a stress strain curve, the area below the curve showing the energy required to fracture the material is known as:

  1. Resilience of the material
  2. toughness of the material
  3. the ultimate strength of the material
  4. hardness of the material
A
  1. toughness of the material
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
  1. A measure of the malleability of a material is often expressed as:
  2. the elastic modulus
  3. toughness
  4. percent of compression
  5. percent of elongation
A
  1. percent of compression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  1. It can be said that a material behaves in certain ways above and below the proportional limit on a stress-strain curve. which of the following is correct?
  2. above the proportional limit a material functions in a plastic manner, while the proportional limit it behaves as an elastic.
  3. above the proportional limit a material functions in an elastic manner, while below the proportional limit it behaves as a plastic.
  4. either 1 or 2 may be true.
A
  1. above the proportional limit a material functions in a plastic manner, while the proportional limit it behaves as an elastic.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  1. Which of the following have a different chemical formula?

a) plaster b) dental stone c) hydrocal d) phosphate- bonded investment e) cristobalite

  1. A,B,ANDC
  2. B,C,ANDE
  3. CANDE
  4. DANDE
A
  1. DANDE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  1. The refractory base in ilay casting investment powder is
  2. silica
  3. sodium chlorides
  4. calcium sulfhate dihydrate
  5. calcium sulfate hemihydrate
A
  1. silica
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  1. The hardest type of dental stone available to the profession is manufactured by
  2. removing it directly from the earth
  3. calcining gypsum by boiling it in a 30% solution
    of calcium chloride
  4. calcining gypsum in open kettles
  5. calcining gypsum under steam pressure in an
    autoclave.
A
  1. calcining gypsum by boiling it in a 30% solution
    of calcium chloride
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  1. What is the major constituent of an inlay pattern wax?
  2. Microcrystalline wax
  3. Ceresin
  4. Carnauba
  5. Beeswax
  6. Paraffin
A
  1. Paraffin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  1. If a wax pattern has been stored in a refrigerator, before
    the investment procedure the wax pattern should
  2. be allowed to return to room temperature
  3. have the margins reheated and readapted
  4. not be allowed to return to room temperature
  5. not be stored in a refrigerator under any circumstances
A
  1. be allowed to return to room temperature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  1. The most important properties of dental wax are

a. melting range
b. thermal expansion
c. mechanical properties
d. flow
e. residual stress

  1. a, b, and c
  2. b, d, and e
  3. a, d , and e
  4. all of the above
  5. none of the above
A
  1. all of the above
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. To impart a hardening heat treatment to a dental gold alloy, the best method is to
  2. pickle the casting in a strong acid
  3. quench the hot casting in cold water
  4. bench cool from casting temperature to room temperature
  5. reheat the cooled casting to 450° C and cool
A
  1. reheat the cooled casting to 450° C and cool
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. According to the American Dental Association Specification for cast gold alloys,
  2. a decrease of the gold content is coupled with a decrease in the mechanical properties, except elongation, which increases
  3. a decrease of the gold content is coupled with an increase in the mechanical properties, except elongation, which decreases
  4. an increase of the gold content is coupled with an increase in the mechanical properties, except elongation, which decreases
  5. there is no correlation between the gold content of the gold alloys and their mechanical properties
A
  1. a decrease of the gold content is coupled with an increase in the mechanical properties, except elongation, which decreases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. If they are of the same composition, which is stronger, cast gold or gold wire?
  2. Cast gold is stronger as it can be heat treated.
  3. Wrought wire is weaker due to the stress
    relieving effect.
  4. Cast gold is weaker as it cannot be cold worked.
  5. Wrought wire is stronger due to the cold working effect.
  6. There is no difference in strength.
A
  1. Wrought wire is stronger due to the cold working effect.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  1. Although gold solders have a lower gold content than the parts being joined by the solder, the properties of the solder joint are essentially the same as the parts except
  2. yield strength
  3. elongation
  4. corrosion resistance
  5. ultimate tensile strength
A
  1. corrosion resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  1. The pure form of gold used in dentistry is known as
  2. class I casting gold
  3. cohesive gold
  4. noncohesive gold
  5. class IV casting gold
A
  1. cohesive gold
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
  1. The carbon content of cobalt-chromium alloys is always below 0.5%, because the effect of carbon on the mechanical properties of these alloys is very strong. This statement consists of two parts, a statement and a reason. Which of the following best describes the statement and reason?
  2. Both statement and reason are correct and related.
  3. Both statement and reason are correct but unrelated.
  4. The statement is incorrect, but the reason is correct.
  5. The statement is correct, but the reason is incorrect.
  6. Both statement and reason are incorrect.
A
  1. Both statement and reason are correct and related.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  1. An orthodontic spring constructed from 18-8 stainless steel will exert twice as much force on a tooth as a comparable gold alloy wire, because the hardness value of stainless steel is twice that of gold alloy wire. This statement consists of two parts, a statement and a reason. Which of the following best describes both the statement and a reason?
  2. Both statement and reason are correct and related.
  3. Both statement and reason are correct but unrelated.
  4. The statement is correct, but the reason is incorrect.
  5. The statement is incorrect, but the reason is correct.
A
  1. The statement is correct, but the reason is incorrect.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

17, Which of the following is the most accurate definition of the term amalgam? Amalgam is

  1. a metallic substance, supplied in the form of fillings, which is mixed with mercury
  2. a metallic substance composed of two or more metals which are mutually soluble in a molten state
  3. an alloy of two or more metals, one of which is mercury
  4. a metallic subtance composed of silver, copper, tin and zinc.
A
  1. an alloy of two or more metals, one of which is mercury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

18, The higher the mercury alloy ratio in dental amalgam,

1, the higher the strength
2, the more matrix material will be formed
3, the more of the y phase will be available
4, the lower the creep value
5, None of the above

A

2, the more matrix material will be formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
  1. Silver and copper in dental amalgam
  2. decrease expansion, fiow, and compressive strength
  3. decrease expansion and compressive strength but increase the flow value
  4. increase expansion and compressive strength
  5. increase flow only
  6. increase expansion but decrease compressive strength
A
  1. increase expansion and compressive strength
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  1. The main achievement in developing the high-copper- content amalgam is the
  2. elimination of the y^ phase
  3. increase in the strength of dental amalgam
  4. decrease in the flow values of dental amalgam
  5. elimination of the fz phase
  6. All of the above
A
  1. elimination of the fz phase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  1. when compared to other materials, dental cements show

a. less strength
b. higher solubility
c. lower resistance to conditions in the oral cavity

  1. a and b
  2. b and c
  3. a and c
  4. a, b, and c
A
  1. a, b, and c
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  1. In zinc phosphate cement liquid the buffering agents are zinc
  2. magnesium
  3. bismuth
  4. aluminum
  5. silicon
A
  1. aluminum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
  1. The zinc oxide-eugenol cements are used as

a. a temporary filling material
b. an insulating base
c. temporary and permanent cementing media
d. a soft tissue pack
e. a root canal sealer

  1. a, b, c, and d
  2. a, b, and c
  3. b, c, and d
  4. All of the above
A
  1. All of the above
24
Q
  1. The incorporation of orthoethoxybenzoic acid and synthetic resins into conventional zinc oxide-eugenol cements is said to

a. increase strength
b. reduce solubility
c. reduce film thickness
d. increase adhesiveness

  1. a and b
  2. b, c, and d
  3. a and d
  4. All of the above
A
  1. a and b
25
Q
  1. Polyacrylic acid is the parent compound of the

1, zinc oxide-eugenol cements
2. zinc phosphate cements
3. cyanoacrylate cements
4. carboxyiate cements

A
  1. carboxyiate cements
26
Q
  1. The most effective dental cement in stimulating growth of secondary dentin is one of the
  2. zinc phosphate cements
  3. calcium hydroxide cements
  4. zinc silicophosphate cements
  5. carboxyiate cements
A
  1. calcium hydroxide cements
27
Q
  1. A solution of one or more resins from the natural gums,
    the synthetic resins, and rosin in an organic solvent is called a
  2. cavity varnish
  3. carboxyiate cement
  4. liner
  5. cyanoacrylate cement
A
  1. cavity varnish
28
Q
  1. A buffering agent for the phosphoric acid of silicate cement is
  2. SiO2
  3. AIPO4
  4. Al203
  5. CaF2
A
  1. AIPO4
29
Q
  1. When a silicate restoration dissolves in the oral fluids, the portion of the set restoration that disintegrates is the
  2. gel matrix
  3. SiO2 particles
  4. CaF2 flux
  5. Zn3 (PO4)2 buffer
A
  1. gel matrix
30
Q
  1. The only real advantage in properties the glass ionomer cement has over a silicate cement is that the glass ionomer cement has
  2. a shorter setting time
  3. greater compressive strength
  4. slightly less solubility
  5. less optical opacity
A
  1. slightly less solubility
31
Q
  1. The initiator of the autopolymerizing resins is
  2. benzoyl peroxide
  3. hydroquinone
  4. methyl methacrylate
  5. p-toluene sulfinic acid
A
  1. benzoyl peroxide
32
Q
  1. The activator (initiator) or the ultraviolet light activated BIS-GMA resins is
  2. a tertiary amine
  3. a peroxide
  4. a methyl ether
  5. hydroquinone
A
  1. a methyl ether
33
Q
  1. the common inorganic phase used in the composites is/are

a. BIS-GMA resin
b. lithium aluminum silicate
c. borosilicate
d. poly (methyl methacrylate)
e. quartz
f. organic silane

  1. a
  2. b and c
  3. a, d, and e
    4.b,c.ande
  4. f and e
  5. a and f
A

4.b,c.ande

34
Q

34, Body and strength are given to the reversible hydrocolloid by

1, potassium sulfate
2, lead peroxide
3, agar
4, borax

A

4, borax

35
Q
  1. The fact that the temperature of gelation of reversible hydrocolloid is lower than the temperature of liquefaction is known as
  2. syneresis
  3. gelling
    3, hysteresis
  4. polymerization
A

3, hysteresis

36
Q
  1. Calcium sulfate in the alginates is a
  2. retarder
  3. reactor
  4. Neither of the above
  5. Both 1 and 2
A
  1. reactor
37
Q
  1. Warm water has which of the following effects on alginates?
  2. No effect
  3. Increase in the gelation time
  4. Decrease in the gelation time
A
  1. Decrease in the gelation time
38
Q
  1. The optimum thickness of polysulflde impression material is
  2. 0.5-1 cm
  3. 2-3 mm
  4. 6-8 mm
  5. 5-10 cm
A
  1. 2-3 mm
39
Q
  1. The oxidizing agent(s) used in the polymerization of polysulfide impression materials is (are)

a. lead octoate
b. tin octoate
c. hydroperoxide
d. lead peroxide

  1. a and b
  2. c and d
  3. b
  4. c
    5.d
A
  1. c and d
40
Q
  1. The advantages of the silicones over the mercaptans include

a. longer working time
b. better odor
c. better esthetic characteristics
d. easier to pour in stone

  1. a and b
  2. a and d
  3. b and c
  4. c and d
A
  1. b and c
41
Q
  1. One of the problems with polyether impression materials
  2. low modulus of elasticity
  3. low coefficient of thermal conductivity
  4. dimensional instability in the presence of moisture
  5. consistency very similar to the reversible hydrocolloids
A
  1. dimensional instability in the presence of moisture
42
Q
  1. An impression compound impression should be poured in gypsum immediately to minimize inaccuracies related to
  2. dehydration
  3. stress relief
  4. syneresis
  5. further setting
A
  1. stress relief
43
Q
  1. An increase in temperature effects the setting time of the zinc oxide-eugenol impression pastes by
  2. shortening the setting time
  3. lengthening the setting time
  4. An increase in temperature has no effect on the setting
A
  1. shortening the setting time
44
Q
  1. The principal difference between the heat-cured denture
  2. basic formulation
  3. cold-cured resins contain an amine accelerator
  4. cold-cured resins contain no initiator
  5. heat-cured resins contain no initiator
A
  1. cold-cured resins contain an amine accelerator
45
Q
  1. The most generally accepted processing temperature for the heat-cured acrylics is
  2. 145 °F - 155 °F
  3. 160 °F - 170 °F
  4. 212 °F
  5. Any of the above
A
  1. 160 °F - 170 °F
46
Q
  1. Inhibitors are added to the monomers of the denture base resins to
  2. activate the monomer
  3. increase shelf life
  4. speed up the reaction
  5. produce a softer polymer
A
  1. increase shelf life
47
Q
  1. Porosity will be seen in what area of a denture base when insufficient packing pressure is used?
  2. In the thickest portion of the denture
  3. At the periphery of the denture
  4. Consistently distributed throughout the denture
  5. At the junction of the teeth and denture base material
A
  1. Consistently distributed throughout the denture
48
Q
  1. If a chemical activator rather than heat is used to generate free radicals from benzoyl peroxide in the initiation step, these polymers are known as
  2. condensation polymers
  3. self-curing polymers
  4. cross-linked polymers
  5. plasticized polymers
A
  1. self-curing polymers
49
Q

49, If an alloy is to be fused to porcelain, it is essential that

1, the compressive strength of the porcelain and alloy be the same
2, the modulus of rupture of the porcelain and alloy be the same
3, the coefficient of thermal expansion of the porcelain and alloy be the same

A

3, the coefficient of thermal expansion of the porcelain and alloy be the same

50
Q

50, Porcelain is superior to plastic as a restorative material, because porcelain abrades more than plastic

1, Both statement and reason are true and related,
2, Both statement and reason are true but not related.
3. The statement is true, but the reason is not true,
4. The statement is false, but the reason is true.

A
  1. The statement is true, but the reason is not true,
51
Q
  1. Porcelain-fused-to-metal restorations are superior to porcelain jacket crowns because a much better aesthetic result is obtainable.
  2. Both statement and reason are true and related.
  3. Both statement and reason are true but not related,
  4. The statement is true, but the reason is not true,
  5. The statement is false, but the reason is true,
A
  1. The statement is true, but the reason is not true,
52
Q
  1. Metallic oxides are included in the composition of dental porcelain to

a, provide a refractory skeleton
b, give color to the porcelain
c. reduce the strength
d, increase the strength

  1. All of the above
  2. b and d
  3. a, b, and d
  4. a, b, and c
  5. None of the above
A
  1. b and d
53
Q
  1. Which of the following have been employed as a pit and fissure sealant?

a. Cyanoacrylate
b. Polyurethane
c. BIS-GMA resin
d. Poly (methyl methacrylate) resin

  1. a and b
  2. a, b, and c
  3. a and c
  4. All of the above
A
  1. a, b, and c
54
Q
  1. According to tests performed on pins in dentin, which pin has the greatest retention?
  2. Cemented pin
  3. Friction pin
  4. Self-threading pin
A
  1. Self-threading pin
55
Q
  1. The pin of choice in endodontically treated teeth is the
  2. cemented pin
  3. friction pin
  4. self-threading pin
A
  1. cemented pin
56
Q
  1. The optimum depth of self-threading pins for an amalgam restoration is
  2. 0.5 mm
  3. 2 mm
  4. 4mm
  5. 5 mm
A
  1. 2 mm
57
Q
  1. The pins designed to depend on the elasticity of the dentin for retention are the

a. cemented pin
b. friction pin
c. self-threading pin

  1. a and b
  2. b and c
  3. a and c
  4. All of the above
A
  1. b and c

dentmat (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions