Page 56 - My FlipBook

54
Some time ago I had the opportunity of examining the
pulps of the teeth of a young elephant, which was dissected
by Sir Astley Cooper. Upon removing the ossification
which had taken place upon the pulps, I found the vessels
to be exceedingly full of blood. There was also a consid-
erable degree of force required to separate the bone from
the pulp, and this strength of union between the pulp and
the ossified part, I have always found to be in proportion to
the size of the tooth.
In the formation of the bone of a tooth the ossific matter
is deposited in strata, one within side the other ; thus a
tooth is formed from the outer part to the inner ; and this
deposition of bone continues until the tooth becomes com-
plete. When the body of the tooth is formed, the pulp
elongates, and takes the form of the fang proper to each
particular tooth, and bone is deposited upon it. It then be-
comes gradually smaller, until it terminates in a point. If
a tooth have two or more fangs, the pulp divides, and the
ossification proceeds accordingly. The cavity within a
tooth, as it is forming, is at first very considerable ; it be-
comes less as the formation advances, until it arrives at a
certain point, when a cavity is left in it extending nearly the
whole length, and retaining the shape of the tooth.
In the crown of the tooth, the cavity is of the same fig-
ure, and it divides into as many canals as there are fan«-s to
the teeth. A canal extends through each fang connected
with the cavity in the body of the tooth. Into this cavity
the nerves and blood vessels enter and ramify upon a mem-
brane of the pulp, which remains to line the cavity after the
formation of the teeth. In this manner the nerves o-ive sen-
sation to the teeth, and the internal parts of them are nour-
ished.