Page 143 - My FlipBook

TREATMENT OF FRACTURES.
129
accident occur to which I have referred, the tooth
coming back with
one corner
missing. It will usually appear as shown in Fig. 139,
where we see the retentive as before indicated the dotted
shaping by
line a, a, the filling itself now observed at b. The distal corner is
absent. A study of this illustration will bring us to the conclusion
that the loss of the corner has not impaired the integrity of the filling.
Of course had the fracture occurred higher up, let us say on a line
with a, the gold would need removal. But the most probable pre-
sentment is as indicated. How shall we
proceed ? Very little is to be
done to the tooth itself, the main reliance into
being upon dovetailing
the
gold filling. Fig. 140 gives an idea of the new cavity ready for
The
filling. sharp angle left by the fracture has been removed so that
the will be more A small rose bur has been
completed filling sightly.
passed to the upper end of the extension at a, and from this point a
groove formed as indicated by the dotted line c. A deep undercut
has been made into the as shown
gold filling, by the dotted line d.
FIG. 138. FIG. 139. FIG. 140.

\&
This undercut is made with a bur, and the gold into which the under-
cutting is carried may be advantageously left rough. It is even possible
by thorough drying to produce an approximation of cohesion between
the new and the old gold, but this is not essential, as a sufficiently
strong mechanical union occurs by careful filling. The first bit of
gold may be placed in the extension at a, and crystal will be found to
serve admirably to begin with.
I will relate an incident which will better convey the importance of
the next which I am about to describe, than
properly filling cavity
mere words of caution. A child of fourteen whom I saw occa-
any
sionally, but who was not in my care, fell and splintered off a portion
of the cutting-edge and labial face of the enamel of a central incisor,
making a cavity which could have been prepared proportionately as
shown in Fig. 141. She was taken to her family dentist, and when I
next saw the girl a gold filling had been inserted of about the size indi-
cated. I asked permission to look at the tooth, but after examination
made no comment, satisfied that any adverse criticism would have
About two
been counted professional jealousy. years later, having
9