Page 267 - My FlipBook

CONTOURING AS A PROTECTIVE MEASURE. 265

Where the decay is of larger extent, however, we have it in our power
to make such physical change in the parts affected as to render future
immunity from decay reasonably certain.
First, it is necessary to separate the teeth well by wedging, to so
enlarge the cavities as to bring their lateral margins well out upon the
lingual and buccal surfaces, and to extend the cervical margins of the
cavities down to or beneath the free margin of the ^um.
Xext, the fillings must be carefully inserted, built out to fully
restore the original contour, and most perfectly finished. When this
has been done and the teeth have returned to their former positions
the approximal surfaces will be in a better condition to resist the influ-
ences of decay than they originally were, for any changes in the char-
acter of the saliva cannot affect the gold, and while the cervical border
of the filling is protected by being constantly covered by saliva the
lateral borders are so far out upon their respective surfaces as to be sub-
ject to the cleansing influences of the lips and tongue.
In addition to this, and scarcely less important, the restoration of
•contour on the approximal surfaces affords normal protection to the
tender gingivae by preventing the lodgment and pressure of food upon
them.
The contour method of filling, based as it is upon physiological,
anatomical, and mechanical principles, has become the accepted method
of operating. Experience has proved it to be the only rational method
of treatment of approximal surfaces, for by it we secure all the desir-
able conditions of preservation of the natural outline of the teeth,
necessary contact, immunity from future decay, and protection of the
gum margins. Its practice involves some sacrifice of healthy tooth
structure along the buccal and lingual aspects, as well as greater ex-
penditure of time in filling and finishing, but the results compensate
for both of these.
To properly perform the operation of filling and restoration of
approximal contour requires not only manipulative skill of a high
order, but also an artistically trained eye in order that the restoration
may in all respects correspond both in extent and form to the original
outline of the tooth ; both of these requisites will be acquired through
frequent repetition. In certain cases, as where the teeth originally were
not quite in contact, the contour may be advantageously exaggerated in
order to close the space, but it should never be less than normal or the
result will not be satisfactory.
In the filling of an approximal surface next to a space, as where a
tooth has been lost, the necessity for full restoration of contour does
not exist and is not absolutely demanded, although a more artistic result
is secured by its performance in all cases.