Treatise on the natural history and diseases of the human teeth : explaining their structure, use, formation, growth, and diseases, in two parts / by John Hunter ; with notes by Thomas Bell.

  • John Hunter
Date:
1839
Catalogue details

Licence: Public Domain Mark

Credit: Treatise on the natural history and diseases of the human teeth : explaining their structure, use, formation, growth, and diseases, in two parts / by John Hunter ; with notes by Thomas Bell. 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.)

    51/127
    than the other.* Any person may be convinced of the truth of these observations by taking two teeth of the same class, but of very different ages, one just completely formed, the other worn down almost to its neck. In the last he will observe the dark spot in the centre, and if as much is cut off from the complete tooth as has been worn off from the old one, the cavity of the young tooth will be found cut through; and on examining the other, its cavity will be found filled up below that surface. Now this observation contradicts the idea of the hole leading into the cavity of the tooth being closed up ; and what is still a further proof of it, I have been able to inject vessels in the cavities of the teeth in very old people when the alveolar process has been gone, and the teeth very loose in the gum. Old people are often found to have very good sets of teeth, only pretty much worn down. The reason of this is, that such people never had any disorder in their teeth, or alveolar processes, sufficient to occasion the falling of one tooth. For if by accident one tooth is lost, the rest will necessarily fail in some degree, even though they are sound, and likely to remain so, had not this accident happened ; and this weakening cause is greater in proportion to the number that are lost. From this observation we see that the teeth support one another.f Of the Continual Growth of the Teeth. It has been asserted that the teeth are continully growing, and that the abrasion is sufficient to keep them always of the same length ; but we find that they grow at once to their full length, and'that they gradually wear down afterwards, and that there is not even the appearance of their continuing to grow. The teeth would probably project a little further out of the gum if they were not opposed by those in the opposite jaw; for in young people who had lost a tooth before the rest had come to their full length, I have seen the opposite tooth project a little beyond the rest before they were at all worn down. It may be further observed, that when a tooth is lost, the opposite one may project from the disposition of the alveolar process to rise higher, and fill up at the bottom of the sockets ; and the want of that natural pressure seems to give that * PI. III. f. 25, 26. t [The filling up of the internal cavity of teeth in old people here alluded to, appears to be consequent upon the loss of substance from the surface. As the superstratum of bone becomes thinner by abrasion, the membrane lining the internal cavity, from which, as I have before shown, the bone of the tooth xoas originally produced, now again resumes its ossific action, and produces a fresh layer of bony matter, which in some cases at length fills the socket, and obliterates the membrane from which it has been secreted. This is particularly the case in sailors who have lived much upon hard biscuits, a circumstance which tends greatly to accelerate this abrasion of the surface, a process perfectly and obviously analogous to that of the wearing of the teeth in graminivorous animals.]