Amalgam

Question 0

What are the particle types in amalgam?

Answer 0

Spherical

Lathe cut

Question 1

What are the two components that react together to form amalgam

Answer 1

Power - silver tin copper zinc

Liquid - mercury

Question 2

Function of copper in the powder

Answer 2

Increases strength and hardness

Question 3

Function of silver and tin in the Y phase?

Answer 3

Reacts with Hg liquid to form amalgam

Question 4

Function of zinc in powder

Answer 4

Scavenger during production

Preferentially oxidises and slag formed

Question 5

Function of Hg in liquid

Answer 5

Triple distilled

Reacts with other metals

Question 6

Range of lathe cut particle types

Answer 6

Fine
Medium
Coarse

Question 7

Define creep

Answer 7

When a material is put under repeated stresses for a long period of time at low stress levels, beneath the elastic limit, it may flow and result in permanent deformation

Question 8

What is the thermal expansion of amalgam?

Answer 8

3x that of the tooth

Question 9

Thermal conductivity

Answer 9

High

Question 10

Radiopaque?

Answer 10

Yes

Question 11

Advantages of spherical cut particles?

Answer 11

Less Hg required
Higher tensile strength
Higher early compressive strength
Less sensitivity to condensation 
Easier to carve

Question 12

Benefits of copper enriched alloys?

Answer 12

Higher early strength
Less creep
Higher corrosion resistance
Increased durability of margins

Question 13

Disadvantages of amalgam

Answer 13

Corrosion
Leakage at margins
Creep
Poor aesthetics