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A TREATISE ON THE HUMAN TEETH, &c. I XT is an incontrovertible truth, that a clean, regular, found fet of teeth contribute greatly to the beauty of the human phyfiognomy ; that they are indifpenfibly neceffary to the prefervation of a clear and diftincl: ar ticulation, and formed by Nature for mafticating and preparing the food for digeftion ; the preservation of them is, therefore, unqueftionably of confequence, and worthy the attention of every human being. Teeth are furnifhed us by nature for/the neceffary purpofe of cutting or grinding the food, and giving a more clear and powerful articulation to the voice. I fhall briefly defcribe their ftructure, number, order of arrangement, time they begin to appear, difeafes and decay, remedies, proper mode of extraction and pre- lervation, &x. &c. I Of the Structure of the Teeth. The human teeth mayjuitly bediftinguifhed by three parts, viz. The body or crown, the neck, and the root, confiding of three different fubftances ; the body is covered with a pearl white vitreous fubftance, com monly called the enamel, which upon the anterior and pofterior furface is about the thicknefs of an Englifh ihilling, encreafing confiderably towards the end of the