Chapter 2 J: Dental Amalgam Flashcards
Amalgam is
An alloy in which mercury appears as a main constituent
Dental amalgam is
Alloy of mercury with silver, tin and varying amounts of copper, zinc, and other minor constituents
Match the finding with the year XVII C:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
D
Match the finding with the year XIX C:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
F
Match the finding with the year 1833:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
A
Match the finding with the year 1855:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
E
Match the finding with the year 1908:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
B
Match the finding with the year 50’s:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
G
Match the finding with the year 60’s:
A: Crawcour brothers crushed silver coins with mercury
B: G.V Black recommended Ag, Sn, Cu, and Zn alloys, and this new alloy was accepted as an obturation material
C: high copper amalgams were introduced, less corrosion and less fractures
D: amalgam was introduced into dentistry
E: towsend added Tin to the mixture improving the mechanical properties
F: Ag introduced into amalgam (pate d’argent)
G: ADA specified percentages of the amalgam components
C
Percentage of silver according to the ADA in the 50’s?
≥ 65
Percentage of tin according to the ADA in the 50’s?
≤29
Percentage of copper according to the ADA in the 50’s?
≤6
Percentage of mercury according to the ADA in the 50’s?
3
Percentage of zinc according to the ADA in the 50’s?
≤2
The two types of amalgam are:
Conventional and high copper
The percentage of copper in conventional amalgam is ?
0-6%
The percentage of copper in high copper amalgam is?
11-22%
Properties of silver include:
- increases resistance, strength, and setting expansion
- reduces shrinkage and setting time
- an excessive amount of Ag can lead to an excessive expansion of the material
What happens to amalgam when it sets in comparison to composite?
Amalgam expands while composite contracts
Properties of tin include:
- reduces strength, hardness, and setting expansion
- increases setting time
Properties of copper include:
- improves hardness and resistance
- reduces tarnish and corrosion
- less fractures and less corrosion
Properties of zinc include:
- its presence is not essential
- improves the color, cleaner aspect
- contaminated with moisture, dissociating H20 into H and O, liberating H as bubbles (secondary expansion)
Properties of mercury include:
Gives the plastic consistency when mixed with other solid crushed metals
Is amalgam soluble or insoluble in the oral cavity?
Insoluble