Page 155 - My FlipBook

DRYING CAVITIES. 151

some such alkali, for a short time, will accomplish
the same thing. Bibulous and blotting paper have
been employed for this purpose ; and by some they
are preferred. Prepared flax has likewise been used.
Either of these is no better than cotton well prepared.

The respect in which the paper is any better than
common cotton, is, that it has the same treatment in
effect as the prepared cotton.
With none of these things can a cavity be made
absolutely dry. It is not necessary to have absolute
dryness to make a good filling, yet a more perfect
filling can be made where that condition is obtained.

Gold takes a better hold upon a perfectly dry, than
upon a moist surface. This is quite apparent in the
following experiment : Place two or three blocks of
gold in any ordinary cavity, wiped as dry as possible,
and press them firmly in place, consolidating them as
much as would be done in filling, and then test the
attachment by removal. Afterward reduce the same
cavity to absolute dryness, take the same amount of
gold, in the same form, and place it in the cavity,

and consolidate as before, at the same point in the
cavity; and then test its attachment in the same

manner. The latter will be found much more firmly
attached than the former.
But it is objected that this is useless, inasmuch as
the natural moisture of the tooth is removed, by pro-