Page 134 - My FlipBook

130 THE TECHNICAL PROCEDURES IN FILLING TEETH.

Instruments.
In the lists of instruments there are three round points of
different sizes from small to large for the more ordinary work,
and then there are two pairs arranged with special reference to
filling occluso-proximate cavities. One of each of these pairs
will fit fairly well into the proximate portion of these cavities,
and the other into the step. They grasp and compress the mass
well in either of these positions. All of them are serrated to
prevent slipping and sliding. These instruments should be used
in all amalgam work.
Heretofore many dentists have used burnishers to pack amal-
gam fillings, thinking they could burnish and amalgam to the
walls of the cavity. This is a popular error. I once supposed
I could do this, and could prove it by burnishing amalgam onto
a tooth-brush handle, causing it to stick so firmly that I could
build a great mass upon it and the whole would cling very
tightly. But on prying this off and examining the surface that
stuck so well with the microscope, I found it full of fine bubbles.
In trying some of these in an aniline dye I found that these bub-
bles became filled with the colored fluid. In trying this in cav-
ities in teeth and breaking the tooth after the amalgam was hard,
I found the same thing occurred. Finally, I became convinced
that the endeavor to make a perfect amalgam filling with a bur-
nisher was a failure. The thing simply can not be done. The
amalgam will flake up from the wall and the adaptation be
imperfect.
Finishing Amalgam Fillings.

When the amalgam filling has stood a few moments to stiffen
in some degree, the surface should be trimmed to form with a
discoid or spoon excavator, if on an occlusal surface, and care-
fully burnished toward the walls, using a light pressure that
will not be liable to move the mass as a whole. If upon an axial
surface, as the buccal, it may very conveniently be trimmed with
the finishing knives and all overlaps removed, and then carefully
but lightly burnished. If an occluso-proximate filling, trim the
occlusal portion before removing the separator, as this work will
give a little more time for the mass to harden to prevent the fill-
ing being crushed by the teeth dropping together.
When the separator is removed the matrix will be