Amalgam

Question 1

What is the composition of conventional amalgam?

Answer 1

65% Ag
6% Cu
29% Sn
2% Zn
3% Hg

Question 2

What is the composition of high copper amalgam?

Answer 2

40% Ag
30% Cu
32% Sn
2% Zn
3% Hg

Question 3

What 2 different morphology of amalgam can you get?

Answer 3

Spherical

Lathe cut

Question 4

What is significant about the gamma 2 phase?

Answer 4

It is susceptible to creep leaving a marginal gap

Question 5

How do you get rid of the gamma 2 phase?

Answer 5

Add more copper

Question 6

What effect does Cu have on amalgam?

Answer 6

It strengthens it

Question 7

What causes amaglam to shrink?

Answer 7

Mercury

Question 8

What causes amalgam to expand?

Answer 8

Crystallisation

Question 9

When is amalgam at its strongest?

Answer 9

24 hours

Question 10

What is released in the gamma 2 phase?

Answer 10

Hg is released in the marginal crevice

Question 11

What part of the high copper phase is more corrosive?

Answer 11

Sn and Hg

Question 12

What is an advantage to corrosion?

Answer 12

it can create a marginal seal

Question 13

in 1998 what did the DOH ban?

Answer 13

Amalgam use in pergnancy

Question 14

What to do if amalgam spillage?

Answer 14

Use alumininium foil

Question 15

What is released during trituration?

Answer 15

Hg

Question 16

What do you do to remove excess Hg?

Answer 16

Carving and burnishing

Question 17

What will happen if the alloy particle size is too small?

Answer 17

You cannot remove the excess Hg but manipulation