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Flashcards in Dental Materials Ch. 10 Deck (22)
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1

if a mold is created for investing and casting does not _ to compensate for the action of the metal alloy, the casting will not fit

a. contract
b. equate
c. expand
d. none

c. expand

2

the most obvious purpose of the investment is to:

a. enlarge the mold by hygroscopic expansion
b. enlarge the mold by thermal expansion
c. form the mold for the casting
d. provide compensation for contraction

c. form the mold for the casting

3

porcelain is "best suited" for:

a. full coverage posterior crowns
b. MODFL onlays
c. veneers on anterior teeth
d. MOD inlays

c. veneers on anterior teeth

4

the crown(s) portion of a dental bridge is called the

a. pontic
b. retainer
c. abutment
d. fixed partial dentur

b. retainer

5

which wax is hard, leave no burnout residue and has a higher melting temperature?

a. boxing
b. rope
c. sticky
d. baseplate
e. inlay

e. inlay

6

during the casting procedure, a wax pattern is heated and the wax melts and flows out of the mold. as the temperature continues to rise, any residual wax is burned away. this is called:

a. shrinkage compensation
b. investing
c. burnout
d. crucible heating

c. burnout

7

identify the correct sequence in the centrifugal casting process

a. add sprue to pattern, place in crucible former, invest and then cast
b. add sprue to pattern, invest, place in crucible former, and then cast
c. place sprue in crucible former, add pattern to sprue, invest and then cast
d. place sprue in crucible former, invest, add pattern to sprue and then cast

a. add sprue to pattern, place in crucible former, invest and then cast

8

a 33% gold alloy may also be expressed as

a. 10 carat
b. 16 carat
c. 333 fine
d. 33 fine

c. 333 fine

9

one type of an all-ceramic restoration is cartable glass. all-ceramic restorations are superior to ceramo-metal restorations in all respects

a. first is true, second is false
b. first is false, second is true
c. both are true
d. both are false

b. first is false, second is true

10

the term used to define the process of firing porcelain powder to become a solid is:

a. liquidating
b. sintering
c. burnishing
d. investing

b. sintering

11

_____ is the pushing of metal against the tooth to close any gap between the tooth and the casting

a. liquidating
b. sintering
c. burnishing
d. investing

c. burnishing

12

which is a fixed indirect restoration?

a. amalgam
b. direct gold (gold foil)
c. onlay
d. composite

c. onlay

13

a restorative material that is placed on the facial surface of anterior teeth to "cover" or hide an esthetic problem is called a:

a. coping
b. veneer
c. buildup (core)
d. pontic

b. veneer

14

another name for a provisional restoration is a _ restoration

a. conditional
b. non-permanent
c. buildup
d. temporary

d. temporary

15

silver is classified as a _ metal

a. non-precious
b. high-noble
c. precious
d. noble

c. precious

16

an advantage of bonding porcelain to metal is

a. a precise fit of the metal
b. the resulting opacity
c. the resulting translucency
d. ease in plaque removal

a. a precise fit of the metal

17

high-gold/high-noble alloys contain _ % gold

a. < 60%
b. > 60%
c. > 50%
d. < 50%

b. > 60%

18

high-gold/high-noble alloys are usually _ metals

a. clear
b. silver
c. yellow
d. b or c

c. yellow

19

low-gold/low-noble alloys contain _% noble metals

a. < 25%
b. > 30%
c. > 25%
d. < 35%

c. > 25%

20

predominantly base metals have _% noble elements

a. < 20%
b. < 25%
c. > 25%
d. > 20%

b. < 25%

21

Low-gold alloys are _ metals

a. clear
b. silver
c. yellow
d. b or c

d. b or c

22

_____ are alloys without any noble elements

a. non-existant
b. predominantly base metals
c. non-precious

c. non-precious