Page 259 - My FlipBook

OPENING CHAMBERS AND CANALS 227

(c) Make the walls of the pulp chamber and canals con-
tinuous.
(d) Pass a small canal cleaner to the apex, or until it
binds, withdraw slightly, give it a half turn and then remove

from the canal,- bringing away as much of the pulp tissue as
possible. Continue this, using larger and larger sizes, as the
canal will permit, broaching or
rasping the sides of the canals,
and gradually enlarging them.

Carry the broach just to the
apex, and no further. The
passage of the broach through
the apical foramen will produce
irritation in the tissues of the

apical space, and consequently
should be avoided.

Fig. 274.—Reaming the canal with Fig. 275.—Enlarging the canals of a
a Kerr twist broach. lower molar with a Nub broach.

(e) Small Canals.—In small canals, where entrance with
a barbed canal cleanser is difficult, change to a spiral broach

reamer, or a twist broach. Start with the smallest size, care-
fully boring in and withdrawing in a direction which will tend
to straighten the canal, gradually changing to larger and larger

sizes, until the canal is thoroughly opened (Figs. 274 and 275).