Sketch of the physiology and pathology of the teeth, as founded on their minute structure / by Robert Nasmyth.

Date:
[1843?]
Catalogue details

Licence: Public Domain Mark

Credit: Sketch of the physiology and pathology of the teeth, as founded on their minute structure / by Robert Nasmyth. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    tubes in dentine, in the cortical substance, in common bone and in the horns of deer, as well as the cells with which they are in connexion, ate a peculiar kind of vessels containing a nourishing and supporting fluid.'' In another part of his work, however, he says, ' with respect to the contents of the canals,'I, as well as Professor Miiller, have found that they consist of an inorganic or earthy substance, which appears white when viewed on a dark ground, but which disappears when the preparation is placed in diluted muriatic acid. When the light falls into these canals, this matter is seen to be composed apparently of infinitdy fine particles, adhering together in lumps.'' How a tube, says Mr A. Nasmyth, can be ' filled with osseous matter,' and at the same time allow of the circulation of a ' nourishing and supporting fluid,' I cannot understand. It must not be forgotten, too, that Retzius allows ' that, in the tooth, no renovation of the material appears to take place.' What end, then, says Retzius, is served by this beautiful organization of the dentine? We have many examples that nature organises structures which have a close affinity to each other, according to one and the same plan; and hence we have, in different parts or organisms, formations, which in some are of great importance, whilst in others they are of much less func- tional significance, or of none whatever. (!) If we hence assume, what is highly probable, that, in bone, the peculiar vessels in question give passage to fluids during the entire life of the ani- mal (or a great part of it),—which fluids contain the solid as well as the liquid materials of the osseous substance,—it does not necessarily follow, that, in the teeth, the same process must be carried on during the whole of life. On the contrary, I am inclined to believe that these vessels in dentine are at their height during the first period of the formation of the tooth, and exer- cise then their more perfect action. At the same time, the existence of a continual vital process in the tooth, as well as in the crystalline lens, cannot be denied [it should be shown which, however, appears to be carried on without any constant exchange of solid matter, and must hence consist in a renovating circulation of the dental fluids. [Without exchange of matter, there can be no renovating circulation.] I refer here to an ob- servation of Gr. H. Weber, published several years ago, and before the existence of the peculiar vessels in question was suspected: —The tooth appears to be penetrated by fluids secreted by the dental germ, and by the membrane surrounding the root ex- ternally, (both of which are abundantly suppHed with vessels). Ihese fluids, without circulating in organic canals, may operate much towards the preservation of the tooth, [it should be shown hoiol «is also towards the decay of the dentine when its composi- tion IS morbid.'