Page 729 - My FlipBook

Fm. 444. Fig. 445.

Figs. 444-447. Outline drawings explaining the opening of the pulp chamber and canals in the
incisor teeth when this is done through the lingual surface.
Fig. 444. The opening to the pulp chamber from the lingual surface as first made with the drill.
Fig. 445. The opening as modified by a fissure bur, which is placed in the drill hole and inclined
so as to cut to the incisal, straightening the approach to the pulp canal.
Fig. 446. The fi.ssvire bur is turned to the deeper jxirtion and a cut made lingually, straightening
the approach of the broach to the apical portion of the canal.
Fig. 447. Finally the incisal point or edge of the pulp chamber is exposed by a fissure bur, or a
12-5-12 hoe, as shown in this figure. This part of the pulp chamber can then be perfectly cleaned and
filled. Generally in the incisor teeth of young persons the drill will strike the pulp some distance
from its incisal end, us shown in Figure 444, and any neglect to expose, clean and fill tliis portion
is certain to result in a discoloration of the crown of the tooth sooner or later.