The superior dental arch is larger than the inferior, so that in the normal condition the teeth in the maxillae slightly overlap those of the mandible both in front and at the sides.

Since the upper central incisors are wider than the lower, the other teeth in the upper arch are thrown somewhat distally, and the two sets do 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 cusp

Cusp (dentistry)

A cusp is an occlusal or incisal eminence on a tooth.Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps...

s 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.