The complete works of John Hunter, F.R.S (Volume 2).

  • Hunter, John, 1728-1793.
Date:
1841
Catalogue details

Licence: Public Domain Mark

Credit: The complete works of John Hunter, F.R.S (Volume 2). Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    each other, that the destruction of the one seems to be always at- tended with that of the other.* In the head of a young subject which I examined, I found that the two first incisor teeth in the upper jaw had not cut the gum, nor had they any root or fang, excepting so much as was necessary to fasten them to the gum, on their upper surface ; and on examin- ing the jaw, I found there was no alveolar process nor sockets in that part. What had been the cause of this I will not pretend to say; whether it was owing to the teeth forming not in the jaw but in the gum, or to the wasting of the fangs. The appearance of the tooth favoured the first supposition, for it was not like those whose fangs are decayed in young subjects, preparatory to the shedding of the teeth ; and as it did not cut the gum, it is reasonable to think it never had any fang. That end from which the fang should have grown was formed into two round and smooth points, having each a small hole leading into the body of the tooth, which was pretty well formed. Of the Articulation of the Lower Jaw. Justunder the beginning of the zygomatic process of each temporal bone, before the external meatus auditorius, an oblong cavity may be observed, in direction, length, and breadth in some measure cor- responding with the condyle of the lower jaw. Before and adjoin- ing to this cavity, there is an oblong eminence, placed in the same direction, convex upon the top, in the direction of its shorter axis, which runs from behind forwards; and a little concave in the direction of its longer axis, which runs from within outwards. It is a little broader at its outer extremitv, as the outer corresponding end of the condyle describes a larger circle in its motion than the inner. The surface of the cavity and eminence is covered with one continued smooth cartilaginous crust, which is somewhat liga- mentous, for by putrefaction it peels off, like a membrane, with the common periosteum. Both the cavity and eminence serve for the motion of the condyle of the lower jaw. The surface of the cavity is directed downward ; that of the eminence downward and back- ward, in such a manner that a transverse section of both would represent the italic letter S. Though the eminence may, on a first view of it, appear to project considerably below the cavity, yet a line drawn from the bottom of the cavity to the most depending part of the eminence is almost horizontal, and therefore nearl? parallel with the line made by the grinding surfaces of ^e teeth n hei^Pe;tJha7;Kand,Whe,n We C°nSlder the ^iculation further w shall find that these two lines are so nearly parallel that theI condyle * [This observation is strictly correct: however ranirllv ft, L sorbed, whether from indigestion, the use of mercurv thp* iSm becomes ab- matter, or that affection which is vulgarly termed scurvy in^Se IT °,fcaI1cn,ous process never becomes exposed (unless it be a dead portion exfoliating ^f0'3' sorption ot the bone always keeps pace with that of the gum.] J' ab*