Henry Gray (18251861). Anatomy of the Human Body. 1918.
not quite correspond to each other when the mouth is closed: thus the upper canine tooth rests partly on the lower canine and partly on the first premolar, and the cusps of the upper molar teeth lie behind the corresponding cusps of the lower molar teeth. The two series, however, end at nearly the same point behind; this is mainly because the molars in the upper arch are the smaller.
FIG. 999 The complete temporary dentition (about three years), showing the relation of the developing permanent teeth. (Noyes.) (See enlarged image)
FIG. 1000 The complete temporary dentition and the first permanent molar. Note the relation of the bicuspids to the temporary molars. (In the seventh year.) (Noyes.) (See enlarged image)
The Permanent Teeth (dentes permanentes) (Figs. 1002,1003).The Incisors (dentes incisivi; incisive or cutting teeth) are so named from their presenting a sharp cutting edge, adapted for biting the food. They are eight in number, and form the four front teeth in each dental arch.