It has been proven that amalgam restoration has the following characteristics:
a- Micro leakage decrease with aging of the amalgam restoration.
b- It is the least techniques sensitive of all current direct restorations.
c- High dimensional changes.
d- A, b and c.
e- A and c.
f- A and b. ***
g. B only.
Research has shown that freshly packed amalgam restorations leak but that this leakage tends to decrease as fillings age.
Cavity varnishes and liners reduce initial leakage of the material.
Form the disadvantages of amalgam is more technique sensitive if bonded ”Sturdevant's art and science of operative dentistry, 5th edition – page 696”
- During electrochemical corrosion of low-copper amalgams, The Sn-Hg phase is oxidized into Sn-O and/or Sn-O-Cl.145,146 The oxychloride species is soluble.
The oxide Precipitates as crystals and tends to fill up the spaces Occupied by the original Sn-Hg phase.
Along the margins Of the amalgam, Sn-O helps seal the space against Microleakage.
- During setting, most amalgams undergo very little Dimensional change.
- The dimensional change during the setting of amalgam is one of its most characteristic properties.
Modern amalgams mixed with mechanical amalgamators usually have negative dimensional changes.
- The only EXCEPTion to this statement is the excessive delayed dimensional change resulting from contamination of a zinc-containing alloy with water during tritura-tion or condensation.
a- Micro leakage decrease with aging of the amalgam restoration.
b- It is the least techniques sensitive of all current direct restorations.
c- High dimensional changes.
d- A, b and c.
e- A and c.
f- A and b. ***
g. B only.
Research has shown that freshly packed amalgam restorations leak but that this leakage tends to decrease as fillings age.
Cavity varnishes and liners reduce initial leakage of the material.
Form the disadvantages of amalgam is more technique sensitive if bonded ”Sturdevant's art and science of operative dentistry, 5th edition – page 696”
- During electrochemical corrosion of low-copper amalgams, The Sn-Hg phase is oxidized into Sn-O and/or Sn-O-Cl.145,146 The oxychloride species is soluble.
The oxide Precipitates as crystals and tends to fill up the spaces Occupied by the original Sn-Hg phase.
Along the margins Of the amalgam, Sn-O helps seal the space against Microleakage.
- During setting, most amalgams undergo very little Dimensional change.
- The dimensional change during the setting of amalgam is one of its most characteristic properties.
Modern amalgams mixed with mechanical amalgamators usually have negative dimensional changes.
- The only EXCEPTion to this statement is the excessive delayed dimensional change resulting from contamination of a zinc-containing alloy with water during tritura-tion or condensation.
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