Page 77 - My FlipBook

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mentioned by Albinus, because similar appearances did not
occur to him, and finding such an imperfect description of
their origin in Mr. Hunter's work
; I have dissected a great
number of infants to ascertain this point, which I think of
the greatest importance.
I have already mentioned that in the youngest foetus I
examined, I observed the rudiments of the four anterior per-
manent grinders, though I could not discover the slightest
appearance of any of the other permanent teeth. But in a
fetus about the eight month, I found the commencement of
the sacs of the incisores and cuspidati ; they were not placed
under the temporary teeth, nor indeed so deep in the jaw,
but within side of them, that is to say, in contact with their
inner surface, lying between that and the internal plate of
the alveolar process, and as Albinus remarks, they were con-
tained in the same sockets with the temporary. In a foetus
between the eighth and ninth months, these sacs were all per-
fectly distinct, and the pulps of the middle incisores were
tolerably advanced, they were elongated a little in the sock-
ets, and the jaws happened to be so far advanced, that the
upper surface of the sockets of the middle permanent incis-
ores were ossified, the lower part remaining still membra-
nous ; the other sockets were less perfect, and exactly in that
state as described by the accurate Eustachius. In children
somewhat farther advanced, I found them nearly as Hemard
mentions, and I confess I did not observe in such young sub-
jects the slightest vestige of those that succeed the tempo-
rary grinders, or any appearance of the middle permanent
ones.
Having fully shewn that the assertions of Eustachius, He-
mard and Albinus are true, I come now to treat more at
large, of the relative situation and connexion of the rudi-
ments of the permanent with the temporary teeth, which