Page 193 - My FlipBook

A STUDY OF TOOTH-ROOTS.
179
many crooked extremities, or ends that assume twists and curves, that
a doubt is engendered, and one may well wonder whether even here
results are it not be that because the
perfect always attained. May
canal-explorer reports that considerable length of canal has been
reached, the operator decides that he must have come to the apex?
May there not still be a crook beyond, which has not been touched by
instruments, however fine? Compare Figs. 207 and 208. In both, the
FIG. 206. FIG. 207. FIG. 208. FIG. 209. FIG. 210.

length
crowns are about similar in size, yet how different the of root.
In Fig. 207 observe the crook which tips the root end almost at right
angles. Look at Fig. 209, with its curved root and crooked end,
and, drawing an imaginary line through the central axis of the crown,
note where it would
emerge through the side of the root were a drill
to follow the same course. Fig. 210 shows a double- rooted cuspid,
and it would not be difficult to a dentist
imagine thoroughly cleansing
and the labial canal, entirely neglecting the because of
filling palatal,
its small size and rarity.
Bicuspids. The first superior bicuspid brings us many problems in
root-filling. Usually the canals are bifurcated, whether the roots are
FIG. 211. FIG. 212. FIG. 213.

or not. Sometimes the canal will be confluent throughout, being con-
nected by a narrow passage, as shown in the diagrammatic section in
211. Here a, a indicates the openings to the canals proper,
Fig.
whilst at b is seen a narrow passage connecting the two. It is this
which is a of interest.
passage point great It is almost always present,
at least in the pulp-chamber occupying the crown. It is safe to
enlarge it, thus completely connecting the two parts of the canal,