These are shown in the illustration at the bottom of this page. Incisors are usually simple teeth, though the crown is sometimes lobed. In many species, incisors are used as pincers for grasping or picking, both in feeding and in grooming. Incisors have been modified in a number of ways. Perhaps the most successful is their enlargement to form chisels used for gnawing.
All mammals have a single canine in each quadrant, if they have canines at all.
When present, the canines are the first tooth in the maxilla. Canines are used by some species as weapons in social displays or fighting. The premolars lie immediately posterior to the canines. In the upper jaw, they are found in the maxillary. They vary considerably in shape and size, from a tiny peg in the mouth of a shrew to a massive crushing or slicing organ in a sea otter or wolf.