Page 52 - My FlipBook

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neck. When viewed laterally the cutting edge is the thm-
est, and the tooth, to the neck of it, increases in thickness.
This gives to the body of the tooth the form of a wedge,
which is its true office, it being used to cut or divide soft
substances.
The enamel is continued farther, and is thicker on the an-
terior and posterior surfaces than on the sides ; it is even
thicker on the forepart than on the back part of the tooth.
The fangs are corneal, and are shorter than those of the
cuspidati.
In the upper jaw the central incisores are much broader
and larger than in the lateral ; in the lower jaw they are all
nearly of the same size, but much smaller than those of the
upper jaw.
The cuspidati are four in number, one ofthem being placed
on the outer side of each of the lateral incisores. The shape
of the crown of a cuspidatus is like that of an incisor, with its
corners rubbed off, so as to end in a point, instead of a broad
edge. The fang is thicker and larger and is more depressed
at the sides, which causes it to appear considerably larger,
when viewed laterally, than when seen in front. The fang,
which is the largest of any of the teeth, may be felt with the
finger, running up a considerable length, and projecting be-
yond those of the other teeth.
The cuspidati of the lower jaw veiy much resemble
those of the upper, both in figure and in length. The ena-
mel covers more of the lateral parts of these teeth than of the
incisores. When they are first formed they are pointed, but
by the friction of each upon the other in mastication, they
become rounded, and sometimes acquire a flat edge.
The use of the cuspidati is not like that of the incisores,
to cut and divide substances, nor like the molares for masti-
cation, but they arc similar to the canine teeth of the car-