Page 711 - My FlipBook

EXPOSURE AND REMOVAT, OK DKNTAI, PUI>P. 369

In the occlusal cavities in the molars in which the decay is
large, often hoe 6-2-23 can be slipped into the opening, and,
using it as a hook, the entire roof of the pulp chamlier may 1)0
pulled away, uncovering the pulp. But when the dentinal cover-
ing is strong, as is usually the case when the opening is only
the exposure of one of the horns of the pulp, the better way
is to enlarge the opening with a small fissure bur. This is passed
into the pulp chamber through the orifice of the exposure, and
when the operator is sufficiently sure in his knowledge of the
anatomy, he may cut aroimd the pulp chamber parallel with its
axial walls and remove the covering in a single piece. Other-
wise the opening may be enlarged by carrying the bur laterally
toward the central portion of the covering of the chamber and
then carrying it around in a circle. Then hoe 6-2-23 may be
passed into the opening and its blade turned under the roof
covering the pulp, the overhang determined, and the cutting
directed, until the whole extent of the chamber is uncovered.
No overhang should be left at any point. In this cutting, the
greatest care should be taken that the bur be not pressed into
the floor of the chamber and its form marred 1)y cutting into it.
It is best to prepare a number of small fissure burs especially
for this work by grinding the ends smooth on a stone while
rapidly rotating in the engine. With these there will be no
danger of marring the floor of the pulp chamber. Wlien the
whole of the roof has been removed, it is generally best to enlarge
somewhat toward the mesio-buccal angle in order to remove the
mesio-buccal horn of the pulp and to give better access to the
mesio-buccal root canal. This may be done most readily and
in the best form by a scraping movement with the cleoid exca-
vator. The case is now ready for the removal of the pulp. Inci-
dentally much of the tissue of the bulb of the pulp, possibly all
of it, will have been removed in doing this cutting, but no attempt
should be made to remove the pulp from the canals until this
cutting is satisfactorily completed and the cavity cleared of all
dentin chips and cuttings. If this is neglected, it will often
happen that these cuttings will get into the smaller root canals
and stop them up so that they can not again be opened. For this
reason all cutting in opening the pulp chamber, especially in
bicuspids and molars in which some of the canals are often very
small, should be fully completed before any effort is made to
remove the pulp from the canals. When in any case it is found
that more cutting for access to some one root canal must be made,
a bit of cotton should be placed loosely in the root canals that

46