Module 3

Question 1

What is the only pure metal that is liquid at room temperature?

Answer 1

Mercury

Question 2

What is an alloy?

Answer 2

mixture of 2 metallic substances

Question 3

Amalgams are classified according to?

Answer 3

composition (low/high copper)

particle size

Question 4

What is Amalgam made of?

Answer 4

Mercury
Silver
Tin
Copper
Zinc (sometimes)

Question 5

One problem with the ZINC in amalgam is?

Answer 5

uncontrolled enlargement of amalgam (creep)

Question 6

One advantage of ZINC?

Answer 6

adds plasticity (eases condensing)

Question 7

The majority of alloys are _____ copper content?

Answer 7

high

Question 8

Copper increases the ______, _____, ______ expansion, and _________ resistance?

Answer 8

strength
hardness
setting
corrosion

Question 9

Low Copper content leads to?

Answer 9

corrosion

Question 10

We want a Gamma __ reaction?

Answer 10

1

Question 11

A Gamma 2 reaction is between ___ and Mercury?

Answer 11

tin

Question 12

A Gamma 1 reaction is between _____ and mercury

Answer 12

silver

Question 13

Percentages of Copper in Low VS High copper amalgams?

Answer 13

4-5% = low
13-30% = high

Question 14

What are the 3 types of particle sizes in amalgam?

Answer 14

Lathe
Spherical
Admixed

Question 15

What is the benefit of Spherical amalgam particles?

Answer 15

can be packed closely together

Question 16

What are 4 advantages to using amalgam restorations?

Answer 16

easy to insert
not technique sensitive
resists fracture
long service life

Question 17

Corrosion of amalgam is decreased when it is?

Answer 17

polished

Question 18

Kaolin in the Ceramic material becomes _____ when wet?

Answer 18

cohesive

Question 19

Fledspar particle in ceramics fuse and form glass of the same shape when subjected to?

Answer 19

high heat

Question 20

What is the difference between Porelain and Ceramic?

Answer 20

Porcelain is fired (baked)

Ceramic is cast (machine milled)

Question 21

What are 2 disadvantages of ceramic/porcelain restorations?

Answer 21

cause wear on opposing enamel

affected by APR (acids containing fluorine)

Question 22

What is the difference between an inlay/onlay?

Answer 22

inlay lays “within” the cusps

only lays “on” cusps

Question 23

Metal reactivity has an _______ relationship?

Answer 23

inverse

Question 24

If a metal has LOW reactivity it has _____ nobility

Answer 24

HIGH

Question 25

Noble metals can resist _____, _____, and _____

Answer 25

corrosion
tarnish
oxidation

Question 26

What are the components of Gold?

Answer 26

Gold
Copper
Silver
Platinum/palladium

Question 27

Copper adds ____ and ______ the melting temp of Gold?

Answer 27

hardness

lowers

Question 28

_____ neutralizes the red color of the copper in Gold restorations?

Answer 28

Silver

Question 29

Platinum and Palladium do what?

Answer 29

increase strength of gold restoration

Question 30

What is the most common base metal used on crowns/bridges?

Answer 30

Nickle-Chromium

Question 31

What is the term used to describe the parts of pure gold in 1,000 parts of Alloy

Answer 31

Fineness

Question 32

Fineness scale:
100% Gold =
75% Gold =
50% Gold =

Answer 32

1000 fine
750 fine
500 fine

Question 33

What is the term used to describe parts of pure gold in 24 parts?

Answer 33

Karat

Question 34

Karat Scale:
100% Gold =
75% Gold =

Answer 34

42

18

Question 35

What type of gold (soft, medium, hard, extra) is used to make crown/bridges?

Answer 35

Hard

Question 36

What type of gold (soft, medium, hard, extra) is used to make simple inlays?

Answer 36

Soft

Question 37

What is the surface where the amalgam and the tooth meet?

Answer 37

Cavo surface

Question 38

We want a ____ fusing temp porcelain so it wont damage the metal?

Answer 38

low