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CHAPTER XXIII.
MANIPULATION OF AMALGAM IN THE MAKING OF A
FILLING.

Definition. Amalgam is a composition of mercury Avith one or
more other metals. It is most commonly combined with two or more
other metals which have been previously alloyed and finely divided
either as shavings or filings to facilitate union with the mercury.
History. Amalgam for the filling of teeth was introduced into
France about the year 1826 by M. Teveau, who called it "silver
paste." This was composed of silver and mercury alone, and must
have given very unsatisfactory results as compared with those se-
cured in the use of our modern alloys.
Reception. The use of amalgam was given a most uuAvelcome
reception by the profession at large, while the converts of the "new
process" were equally emphatic in their praise of the new filling
which "would certainly cheapen dentistry, and harm the profession."
But time has proved amalgam to be a blessing to the poorer classes
in that it brings dentistry within the reach of all purses and has
thereby proved of advantage to the dental profession by broadening
its field of usefulness.
While amalgam has many faults and should generally be avoided
when finance will permit, the fact still remains that more teeth have
been saved through its use than with any other filling material.
However the percentage of salvage is greater with gold, which
forces amalgam to second place.
The Properties of Amalgam which render it of value as a filling
material are: First, its plasticity eliminating access form in cavity
preparation, making possible the building up of lost contours in inac-
cessible places in the mouth, where convenience and access forms are
hard to secure, sufficient for the manipulation of gold either co-
hesive or as an inlay; second, its property of being but slightly af-
fected by the oral fluids, and the fact that it is fairly stable as to
bulk and shape; and last, but not least in the minds of many pa-
tients, we are sorry to say, is its cheapness, as most dentists see fit
to build fillings of amalgam for a much smaller fee than gold.
The Objections to Amalgam are: Its tendency to discolor both
as to its exposed surface and the teeth with which it has been filled
due to slight leakage with old fillings; its comparatively large ex-
pansion and contraction range; its continued flow under load; its
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