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 Incisor Incisors (from Latin incidere, "to cut") are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.
Contents
Function
In many omnivorous mammals, such as the human, they are adapted for shearing sharply. In cats, the incisors are small; biting off meat is done with the canines and the carnassials. In elephants, the upper incisors are modified into curved tusks, just as is the case with Narwhals, where normally one of them develops into a straight and twisted tusk. The incisors of rodents grow throughout life and are worn by gnawing.
Number and types of incisors
In humans
Adult humans normally have eight incisors, two of each type. The types of incisor are:
- maxillary central incisor (upper jaw, closest to the center of the lips)
- maxillary lateral incisor (upper jaw, beside the maxillary central incisor)
- mandibular central incisor (lower jaw, closest to the center of the lips)
- mandibular lateral incisor (lower jaw, beside the mandibular central incisor)
Children with a full set of deciduous teeth (primary teeth) also have eight incisors, named the same way as in permanent teeth. Young children may have from zero to eight incisors depending on the stage of their tooth eruption and tooth development.
In non-human animals
Among other animals, some other primates, cats and horses have twelve. Rodents have four, while Foxes have nine. Rabbits and hares (lagomorphs) were once considered rodents, but are distinguished by having eight—one small pair, called "peg teeth", is located directly behind the most anterior pair. Incisors are used to bite off tough foods, such as red meat.
Additional images
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Mouth (oral cavity)
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Left maxilla. Outer surface.
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Base of skull. Inferior surface.
See also
Dental anatomy (TA A05.1.03, GA 11.1112–1124) Teeth Maxillary teeth Incisor: Central incisor, Lateral incisor, Canine
Premolar: First premolar, Second premolar
Molar: First molar, Second molar, Third molarMandibular teeth Incisor Central incisor, Lateral incisor, Canine
Premolar: First premolar, Second premolar
Molar: First molar, Second molar, Third molarParts Crown: Cusp (Cusp of Carabelli)
Pulp · Root canal (Apical foramen)
Cementoenamel junction · Enamel · Dental-enamel junction · Dentin · Dental papilla
Dental alveolusCategories:- Types of teeth
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Look at other dictionaries:
Incisor — In*ci sor, a. Adapted for cutting; of or pertaining to the incisors; incisive; as, the incisor nerve; an incisor foramen; an incisor tooth. [1913 Webster] … The Collaborative International Dictionary of English
incisor — (n.) cutting tooth, 1670s, from M.L. incisor a cutting tooth, lit. that which cuts into, from L. incisus, pp. of incidere (see INCISION (Cf. incision)). Inscisours as the name of a cutting tool is attested from early 15c … Etymology dictionary
Incisor — In*ci sor (?; 277), n. [NL.] (Anat.) One of the teeth in front of the canines in either jaw; an incisive tooth. See {Tooth}. [1913 Webster] … The Collaborative International Dictionary of English
INCISOR — idem cum Carptore Scissore, Structore, quas voces vide. In Gallia Incisoris Regis insigne furcilla est cum cultro decu ssata. Cultri vero Incisorii duo decussatim locati, laminisque argenteis et ex auro capulis instructi, Abbatiae Quedelinburgiae … Hofmann J. Lexicon universale
incisor — |ô| s. m. Aquele ou aquilo que corta … Dicionário da Língua Portuguesa
incisor — ► NOUN ▪ a narrow edged tooth at the front of the mouth, adapted for cutting … English terms dictionary
incisor — [in sī′zər] n. [ModL < L incisus (see INCISE) + OR] a cutting tooth; any of the front teeth between the canines in either jaw: in humans there are eight incisors: see TEETH … English World dictionary
incisor — UK [ɪnˈsaɪzə(r)] / US [ɪnˈsaɪzər] noun [countable] Word forms incisor : singular incisor plural incisors medical one of the sharp teeth at the front of your mouth, used for cutting and biting. The incisors are between four sharp teeth called… … English dictionary
incisor — SYN: i. tooth. [L. incido, to cut into] central i. the first tooth in the maxilla and mandible on either side of the midsagittal plane of the head. Hutchinson incisors SYN: Hutchinson teeth, under tooth. lateral i. SYN: second i.. second i … Medical dictionary
incisor — noun Date: 1666 a front tooth typically adapted for cutting; especially one of the cutting teeth in mammals located between the canines when canines are present see tooth illustration … New Collegiate Dictionary
