Page 188 - My FlipBook

METHODS OF FILLING TEETH.
174
against its reverse side. In fact, the disk on the engine in my hands
is more useful than any other finishing appliance. I may say here
that in spite of the undoubted ingenuity which has been displayed in
the invention of disk-carriers, the best for all practical purposes is
still the original simple screw-mandrel. Instead of using a screw-
driver, however, the disk may be placed or removed by having the
mandrel in the engine, and holding the disk whilst the engine is started
quickly.
After a medium of disk for off the mass
using grade taking surplus
of gold, follow with one made from the finest pouncing-paper. This
will a Nevertheless, a luster still should
produce good polish. higher
be attained by use of a strip of chamois well chalked. For this the
best material is what is known as ' ' whiting. ' '
I do not like files, either between the teeth or on labial surfaces.
In the former they are apt to leave flat planes, and in any event they
make scratches, which must be removed with the
finally sand-paper,
so that the disk may as well be chosen at the outset. Occasionally a
file may be needed for making sufficient space in which to revolve a
disk or a still, even in these cases I a saw, which,
pass strip ; prefer
having no cutting sides, removes only the rough excrescences which
prevent the ingress of the sand-paper. The approximal trimmer is
a humane and valuable instrument. Where the cervical
margin
reaches to or passes the gum-margin, the over-build of gold should
be removed with the trimmer rather than with
carefully approximal
a sand-paper strip or disk, either of which will so wound the gum that
not only will it remain in a state of irritation for several days, but
frequently recession is induced. This instrument is also essential for
the finishing of festoon fillings. In these cases it will often be better
to remove the dam as soon as the is for the reason that
filling placed,
the clamp interferes with the work. With care, a fine finish may be
achieved without wounding the gum. This is, however, a difficult
place to contend with. With the approximal trimmer remove the
excess of even that mean
gold carefully, though may slowly, per-
fecting the gingival margin and working from the gum toward the
incisive end of the tooth, thus avoiding wounding the gum and
consequent hemorrhage. The gold trimmed to approximately proper
proportions, resort to the smallest disks, placed on the mandrel as
before directed. the of the disk near the
Placing edge gum, slight
pressure will cause it to bend, so that as it is revolved it finishes the
surface of the the of the disk if even
gold, edge required passing
under the gum-margin without wounding it. A final polish may
be produced with the polishing-powders on soft-rubber disks, or in
connection with wood points. The rubber cup, Fig. 200, is invalu-
able.