“The first four teeth, being cutting teeth (incisors), are called by the Greeks _tomici_. These are flanked on both sides by one canine. Beyond this there ordinarily exist, on both sides, five grinders, except in the case of those persons in whom the last molars, which commonly are cut very late, have not yet appeared. The incisors and the canines are fixed with one single root; but the molars at least with two, some even with three or four. In general, the shorter the tooth, so much the longer is its root. A straight tooth commonly has a straight root, a curved tooth has it generally curved. The root of a temporary tooth produces in children a new tooth, which usually pushes out the first; sometimes, however, the new tooth appears either above or below it.” In the seventh chapter Celsus treats of fractures in general, but in particular of those of the lower jaw. “To reduce a fracture of this bone, it should be pressed in a proper manner, from the inside of the mouth and from the outside, with the forefinger and thumb of both hands. Then in the case of a transverse fracture (in which case generally an unevenness in the level of the teeth is produced), it is necessary, after having set the fragments in place, to tie together the two teeth nearest to the fracture with a silk thread, or else, if these are loose, the following ones. After this, one should apply externally, on the part corresponding to the lesion, a thick compress, dipped in wine and oil and sprinkled with flour and powdered olibanum. This compress is to be fixed by a bandage or by a strip of soft leather, with a longitudinal slit in the middle to embrace the chin, the two ends being tied together above the head. The patient must fast the first two days; then he may be nourished with liquid food, but in small quantities, abstaining, however, completely from wine. On the third day it is necessary to take off the apparatus, and after having fomented the part with the steam of hot water, to replace it. The same is to be done on the fifth day, and so on, until the inflammation has subsided, which generally happens from the seventh to the ninth day. After the symptoms of inflammation have vanished, the patient may take abundant nourishment; he must, however, abstain from chewing until the fracture is completely consolidated; and, therefore, he will continue to nourish himself with soups and like food. He must also entirely abstain from speaking, especially during the first few days. Fractures of the jaw commonly heal from the fourteenth to the twenty-first day.