1. DENTAL AMALGAM

2. Terminology

Silver paste

an alloy, one of the constituent of
which is mercury

an alloy made by mixing Hg with
Ag-Sn dental amalgam alloy

3. Components

1. Silver ( Ag) -increase expansion
- retards setting time
- enhances strength
- decrease flow
- resist tarnish/corrosion

4. 2. Copper (Cu)- unites with Hg with
difficulty

5. 2. Copper- unites with Hg with
difficulty
- reduces setting time

6. 2. Copper- unites with Hg with
difficulty
- reduces setting time
- increases expansion

7. 2. Copper- unites with Hg with
difficulty
- reduces setting time
- increases expansion
- increases strength and
hardness

8. 2. Copper- unites with Hg with
difficulty
- reduces setting time
- increases expansion
- increases strength and
hardness
- reduces flow

9. 2. Copper- unites with Hg with
difficulty
- reduces setting time
- increases expansion
- increases strength and
hardness
- reduces flow
-tarnishes readily

10. 3. Tin (Sn)

11. 3. Tin - unites readily with Hg

12. 3. Tin - unites readily with Hg
-retards setting time

13. 3. Tin - unites readily with Hg
-retards setting time
-improves plasticity

14. 3. Tin - unites readily with Hg
-retards setting time
-improves plasticity
-reduces expansion

15. 3. Tin - unites readily with Hg
-retards setting time
-improves plasticity
-reduces expansion
-increases flow

16. 4. Zinc

17. 4. Zinc (Zn)- combines readily with
Hg

18. 4. Zinc - combines readily with Hg
-causes expansion

19. 4. Zinc - combines readily with Hg
-causes expansion
-increases setting time

20. 4. Zinc - combines readily with Hg
-causes expansion
-increases setting time
-increases flow

21. 4. Zinc - combines readily with Hg
-causes expansion
-increases setting time
-increases flow
-inhibits oxidation

22. 4. Zinc - combines readily with Hg
-causes expansion
-increases setting time
-increases flow
-inhibits oxidation
-decreases porosity

23. Classification

24. Classification
1. Amalgam alloy particle geometry
and size

25. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut,

26. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical

27. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content

28. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content
e.g. Low Copper (conventional
amalgam),

29. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content
e.g. Low Copper (conventional
amalgam), High Copper

30. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content
e.g. Low Copper (conventional
amalgam), High Copper
3. Zinc Content

31. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content
e.g. Low Copper (conventional
amalgam), High Copper
3. Zinc Content
e.g. Zinc,

32. Classification
1. Amalgam alloy particle geometry
and size
e.g. Lathe-cut – regular, fine
microfine cut, Spherical
2. Copper Content
e.g. Low Copper (conventional
amalgam), High Copper
3. Zinc Content
e.g. Zinc, Zinc-free

33. Alloy- Mercury Ratio

34. Alloy- Mercury Ratio

irregular particle pack poorly and
require a large amount of Hg
(50%-60%)

35. Alloy- Mercury Ratio

irregular particle pack poorly and
require a large amount of Hg
(50%-60%)

precapsulated amalgam
(spherical)has 42%- 45% mercury

36. Mercury rich mixtures – uses
squeeze cloth to remove excess
mercury

37. Mercury rich mixtures – uses
squeeze cloth to remove excess
mercury
1960 -Eames technique or no
squeeze cloth technique

38. Trituration

39. Trituration

process of manual mixing of alloy
with Hg

40. Trituration

process of manual mixing of alloy
with Hg

done by proportioning mercury and
Hg into a mortar and grinding the
mixture with a pestle

41. Trituration

process of manual mixing of alloy
with Hg

done by proportioning mercury and
Hg into a mortar and grinding the
mixture with a pestle

mixing of alloy with mercury

42. Types of Trituration

43. Types of Trituration
1. Hand

44. Types of Trituration
1. Hand
2. Mechanical

45. Types of Trituration
1. Hand
2. Mechanical –use of Amalgamator

46. Types of Trituration
1. Hand
2. Mechanical –use of Amalgamator

reusable capsule

47. Types of Trituration
1. Hand
2. Mechanical –use of Amalgamator

reusable capsule – a hallow tube
with rounded ends constructed as
two pieces that could be friction fit
or screwed together

48. 
precapsulated (preproportioned)-

49. 
precapsulated (preproportioned)-
the components are separated in
the capsule by a special diaphragm
that is broken when the capsule is
placed in an amalgamator.

50. Reaction

51. Reaction
Mercury+Silver-Tin

52. Reaction
Mercury+Silver-Tin Silver-Tin
phase+ Silver-mercury phase + Tin-
mercury phase

53. Reaction
Mercury+Silver-Tin Silver-Tin
phase+ Silver-mercury phase + Tin-
mercury phase

Silver-tin phase is called the
gamma phase, composed of
unreacted alloy particle

54. 
Silver-mercury phase is called the
gamma one

55. 
Silver-mercury phase is called the
gamma one

Tin-mercury phase is called the
gamma two

56. 
Silver-mercury phase is called the
gamma one

Tin-mercury phase is called the
gamma two

amalgam can be thought of as
particles of gamma surrounded by
or bonded together by a matrix of
gamma1 and gamma2

57. Hardening of amalgam

58. Hardening of amalgam
2 Phenomena

59. Hardening of amalgam
2 Phenomena
1. Solution

60. Hardening of amalgam
2 Phenomena
1. Solution
2. Crystallization

61. Hardening of amalgam
2 Phenomena
1. Solution
2. Crystallization

when Hg comes in contact with
amalgam alloy, the particles
(gamma) are wet by mercury and
begins to absorb it.

62. 
the solution of mercury into silver-tin
particles leads to the formation of
the surface of Ag-Hg and Sn-Hg
phases

63. 
the solution of mercury into silver-tin
particles leads to the formation of
the surface of Ag-Hg and Sn-Hg
phases

the crystallization of the gamma1
and gamma2 phases and their
subsequent growth leads to
hardening of amalgam

64. Mercury Management

65. Mercury Management
Sources of Mercury Hazards

66. Mercury Management
Sources of Mercury Hazards
1. Mercury vapors released from
stored materials

67. Mercury Management
Sources of Mercury Hazards
1. Mercury vapors released from
stored materials
2. Amalgamator aerosols

68. Mercury Management
Sources of Mercury Hazards
1. Mercury vapors released from
stored materials
2. Amalgamator aerosols
3. Spillage during restoration
procedure

69. Mercury Management
Sources of Mercury Hazards
1. Mercury vapors released from
stored materials
2. Amalgamator aerosols
3. Spillage during restoration
procedure
4. Amalgam removal and
replacement

70. 5. Amalgam waste on cotton rolls

71. 5. Amalgam waste on cotton rolls
6. Amalgam and mercury in
plumbing and sewer system

72. 5. Amalgam waste on cotton rolls
6. Amalgam and mercury in
plumbing and sewer system
7. Amalgam scrap container

73. 5. Amalgam waste on cotton rolls
6. Amalgam and mercury in
plumbing ans sewer system
7. Amalgam scrap container
8. Mercury trapped in tiles and
carpeting

74. THAT'S ALL FOLKS