The anatomy, physiology, and diseases of the teeth.

  • Bell, Thomas, 1792-1880
Date:
1831
Catalogue details

Licence: Public Domain Mark

Credit: The anatomy, physiology, and diseases of the teeth. Source: Wellcome Collection.

    24/402 (page 4)
    A STRUCTURE OF fices of the different teeth require. ‘The part where the body and crown unite is termed the neck.* There are two distinct substances which enter into the composition of the teeth, essentially differing from each other in structure as well as in chemical compo- sition; the one being organized, the other crystalline. The first,} of which the mass of the tooth consists, is true Bong; the second, which, from its appearance, is called enamex,{ forms only a thin layer over the body of the tooth, to which part it is distinctly re- stricted. The bony substance is of an extremely hard, dense structure; and, like other bones, is composed of an earthy and a cartilaginous portion. ‘The earthy mat- ter may be readily dissolved by immersion in dilute mineral acid; and the cartilage which remains, still retains its form, and is found to be more solid and compact than the same substance as it exists in other bones. The fracture of this bone is shining, and slightly conchoidal. On a minute examination, and particularly if aided by the application of heat, it is seen to consist of concentric layers, the disposition of which is parallel to the surface of the tooth. It is ex- tremely indestructable; so much so, that on opening barrows and other ancient places of sepulture, the teeth are frequently found to have undergone scarcely any perceptible decomposition. The enamel is an extremely hard, milky white, se- mitransparent substance, composed almost exclusively of earthy salts, principally phosphate of lime, contain- ing a trace only of animal matter. It is the hardest of all animal substances, and consists of minute fibrous