Page 150 - My FlipBook

134 THE TREATMENT OF TEETH
amalgam with a cement lining, and it is desired to
dispense with the rubber dam.
Combination {Mixture) of Copper and Allojj Amal-
gam.—It might naturally be thought that a mixture
of copper amalgam and an alloy amalgam would
increase the merits and reduce the defects of either
used singly. It might be supposed that the ad-
mixture of copper would reduce the flow and shrink-
age of an alloy amalgam, and that the alloy would
reduce the wasting away or rotting of the copper.
The writer has made a large number of such fillings
during the last eight years, and finds that his ex-
pectations have been fulfilled. It has been stated
that this mixture is of no value, inasmuch as the
filling acts just like either a copper or an alloy
amalgam, depending on the proportions of the mix.
Either the filling shows all the wasting and rotting
of a copper amalgam, or else it shows all the curl-
ing up of margins associated with an alloy.
The writer's experience is that whenever the
filling wastes away, this process is very slow com-
pared to copper amalgam ; moreover, good edges
are maintained, and when no waste takes place,
any curling up of edges is very slight, and appa-
rently of little moment. The writer's method
is to soften and rub the copper amalgam in the
usual way, then to mix the alloy with mercury to