A manual of dental anatomy : human and comparative / by Charles S. Tomes.

Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: A manual of dental anatomy : human and comparative / by Charles S. Tomes. 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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    contents of the dentinal tubes through the medium of large masses of protoplasmic matter found at the margins of the enamel and dentine. But although there are various reasons for suspecting that enamel is not completely out of the pale of nutrition from the moment that a tooth is cut, yet further observations ai-e needed before the activity and importance of the cement substance demonstrated by Bodecker can be held to be fully established. Klein remarks that the enamel cells, like all epithelial cells, being separated from one another by a homo- geneous interstitial substance, it is clear tiiat the remains of this substance must occur also between tlie enamel prisms ; in the enamel of a developing tootli the interstitial substance is larger in amount than in the fully formed organ. It is improbable tliat nucleated protoplasmic masses are contained in the interstitial substance of the enamel of a fully-formed tooth, as is maintained quite recently by Bodecker. Von Ebner, who has recently investigated the subject of enamel {Sitzungsherichte d. Kaiser. A/cad. 1889), holds that there is an uncalcified cement substance between the prisms, which appears to be traceable into con- tinuity with Nasmyth's membrane, which, however, acids cause to peel oft', so tliat this continuity may be merely apparent. The study of the development of marsupial enamel, to be alluded to at a future ])age, by showing that the enamel is penetrated by soft tissue differently placed, also tends to throw doubt upon Bodecker's interpretation. W. J. Barkas {Monthly Review of Dental Siirgeri/, 1874) has also perhaps had under observation this cementing substance; he believes that the enamel prism.s of human enamel are tubular, wifcli minute canals running along their axes. On the whole tlie prisms are parallel, and run Irom the surface of the dentine continuously to that of the enamel.