Incisor

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Incisor
Permanent teeth of right half of lower dental arch, seen from above.
The permanent teeth, viewed from the right.
Latin	dentes incisivi
Gray's	subject #242 1115
MeSH	A14.549.167.860.425

Incisors are the first kind of tooth in heterodont mammals.

[edit] Function

In many herbivorous or omnivorous mammals, such as the human and the horse, they are adapted for shearing sharply. In cats, the incisors are small and do not do much; biting off meat is done with the canines and the carnassials. In elephants, the upper incisors are modified into tusks. The incisors of rodents grow throughout life and are worn by gnawing.

[edit] Number and types of incisors

[edit] In humans

Humans normally have eight incisors, two of each type. The types of incisors are:

• maxillary central incisor
• maxillary lateral incisor
• mandibular central incisor
• mandibular lateral incisor

[edit] In animals

Among other animals, some other primates, cats and horses have twelve. The rodents have four; lagomorphs were once thought to be rodents, but are distinguished by having eight.

[edit] See also

• canine tooth
• molar