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SECTION V.

PHYSIOLOGICAL OBSERVATIONS UPON STUMPS OF TEETH
AND THE MANNER OF PREPARING THEM FOR INSERTION
OF ARTIFICIAL TEETH UPON THEM.

In the first part of this work, I noticed that the teeth were
possessed of two sources of support.
The body and crown
of the tooth are supported by the blood-vessels, nerve, &c,
which occupy the cavity in the interior-of the tooth, whilst
the fang, root, or stump, receives a share oT its support
from its external membrane, which covers
it and lines the
alveolus.
The cortex striatus or enamel of the tooth, is, as
regards the sanguinious circulation, entirely extraneous, hav-
ing no sensibility whatever, and can be operated upon with-
out the least pain being- perceived in it.
It has the same re-
lation to the body of the tooth, that the cuticle has to the
cutis, or the epidermis to the dermoid
tissue : the latter is
much thicker on parts which are subject to the application of
pressure or hard substances, as the feet, and
soles of the
palms of the hands. But the enamel is formed at first per-
fectly adequate to sustain the pressure which falls upon it in
mastication, and, under all ordinary circumstances, it com-
pletely protects the bony substance of the tooth from the
contact of injurious substances. The cuticle, if removed,
may be, and is reproduced from the vessels of the cutis, but the
cortex striatus, or enamel of the tooth, is formed from a mem-
brane, investing, as we have before said, the substance of the
tooth, which, as its retention upon the tooth would be incompat-
ible to the function of the tooth, is, after the perfect formation of
the enamel, entirely absorbed away, leaving the enamel per-
fectly and beautifully formed, and attached to the substance