Page 262 - My FlipBook

230 — THE TREATMENT OF PULPS .

2. Indestructible in the fluids entering at the apex, or
through the pulp chamber (in case of leaky fillings)
3. Easy of introduction.
Antiseptic in character.
Colorless.

Easy of removal (in case of trouble arising later).
Negative to the penetration of the Roentgen ray.
Rule.—Endeavor always (a) to completely
seal the apical foramen, (b) avoid forcing the
material through, and (c) to so adapt the mate-
rial to the walls of the canal that all air will be

excluded and the canal for its entire length be
hermetically sealed. The radiograph is valuable
for ''checking up" root-canal work at its termi-
nation.
Technic.

Several methods of filling canals will be de-
scribed, one for large and the other for small
canals.
I. Fn.LING LARGE CANALS.—Gutta-
percha points. (Black's method.)

(a) Measure the diameter of the apical fora-
Fig. 276.
Measuring the men. Pass a small, smooth broach, or canal
length of the plugger, to the apex If it passes through,
change to a size larger, or two sizes larger, con-
tinuing until one is found which will pass just short of the

apical foramen.
(b) Measure the length of the canal. Pass a small,
smooth broach, or a hooked extractor, if the size of the canal
will permit, to the apical foramen, catching the hook over
the apex, if the latter instrument is used. A small piece of
cardboard or rubber dam encircling the shaft of the broach

is moved until it is in contact with the crown of the tooth.