Page 142 - My FlipBook

138 OPERATIVE DENTISTRY
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ward the center of the filling as possible and drawn directly outward
and over the edge of the filling out to the external enamel surface.
The Finishing Knife should be engaged into the substance of the
gold and drawn from the gum and at the same time outward, tak-
ing off only a small portion of gold at each cut.
Coarse Abrasives, as carborundum stones and coarse disks and
strips, should be abandoned as soon as a near approach to the cavo-
surface angle is reached, and the files, plug-finishing burs, and knife
edged instruments resorted to, to bring into view the exact cavity
outline, after which the finer strips and disks should be employed to
bring gold and tooth substance to an exact level at the cavo-surface
angle for the entire cavity outline.
Finishing Strips in the Proximal. To reduce the quantity of gold
from contact point to the gingival, a coarse finishing strip sufficient-
ly narrow to reach from the gingival outline to near the contact
point only, is of advantage. This strip is introduced by sharpening
one end and passing through the embrasure below contact point and
then drawn back and forth till the desired surface is secured.
Fine narrow linen strips are then used in the same way to give
a final finish to this place of difficult access.
When the Entire Cavity Outline Has Been Exposed and the sur-
face otherwise made ready for the final finish the separator should
be tightened another degree, when it will be found that a broad fine
linen strip will easily pass contact point. This should be given three
or four sweeps with this broad strip not too tightly drawn, when
the contact point should be considered finished.
The separator should be gradually loosened and removed, the rub-
ber dam removed and the filling tested for occlusion and articula-
tion and properly shaped. The filling should then receive a thorough
finish, with wood points, leather wheels and tooth cleaning brushes,
carrying first pumice, then whiting, till the surface of the filling is
as smooth as the external enamel surface.