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14li HUNTER ON THE TEETH.
marks of four or five Teeth, which occupy the whole length of
the Upper-Jaw, and all that part of the Lower which lies before
the Coronoid Process, for the fifth Tooth is somewhat under
that process.
These five marks become larger, and the Jaw bones of course
increase in all directions, but more considerably backwards ; for
in a Foetus of seven or eight months, the marks of six Teeth in
each side of both Jaws are to be observed, and the sixth seems
to be in the place where the fifth was ; so that in these last four
months the Jaw has grown in all directions in proportion to the
increased size of the Teeth, and besides has lengthened itself
at its posterior end as much as the whole breadth of the socket of
that sixth Tooth.
The Jaw still increases in all points till twelve months after
birth, when the bodies of all the six Teeth are pretty well formed
but it never after increases in length between the symphysis
and the sixth Tooth ; and from this time too, the Alveolar Pro-
cess, which makes the anterior part of the arches of both Jaws,
never becomes a section of a larger circle, whence the lower part of
a child's face is flatter, or not so projecting forwards as in the adult.
After this time the Jaws lengthen only at their posterior
ends ; so that the sixth Tooth, which was under the Coronoid
Process in the Lower-Jaw, and in the tubercles of the Upper-
Jaw of the Fcetus, is at last, viz. in the eighth or ninth year,
placed before these parts ; and then the seventh Tooth appears
in the place which the sixth occupied, with respect to the Coro-
noid Process, and tubercle ; and about the twelfth or fourteenth
year, the eighth Tooth is situated where the seventh was placed.
At the age of eighteen, or twenty, the eighth Tooth is found
before the Coronoid Process in the Lower-Jaw, and under, or
somewhat before the tubercle in the Upper-Jaw, which tubercle
is no more than a succession of sockets for the Teeth till they
are completely formed.
In a young child the cavity in the temporal bone for the
articulation of the Jaw is nearly in a line with the Gums of the
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