also spelled  Dentin,  

      in anatomy, the yellowish tissue that makes up the bulk of all teeth. It is harder than bone but softer than enamel and consists mainly of apatite crystals of calcium and phosphate. In humans, other mammals, and the elasmobranch fishes (e.g., sharks, rays), a layer of dentine-producing cells, odontoblasts, line the pulp cavity of the tooth (or, in the case of sharks, the toothlike scale) and send projections into the calcified material of the dentine; these projections are enclosed in tubules. Sensitivity to pain, pressure, and temperature is transmitted via the odontoblastic extensions in the tubules to and from the nerve in the pulp chamber. Secondary dentine, a less well-organized form of tubular dentine, is produced throughout life as a patching material where cavities have begun, where the overlying enamel has been worn away, and within the pulp chamber as part of the aging process.

      In nonmammalian vertebrates, enamel is lacking; the tooth crown is covered instead with vitrodentine, a compound related to dentine, which is harder than dentine but somewhat softer than enamel.

      A few animals, such as flounder and cod, have vasodentine, in which tubules are lacking, and the dentine is nourished directly by capillaries. Though more efficient nutritionally, this type of dentine is softer and less resistant to disease than tubular dentine. The material composing the toothlike scales of sharks and related fish is also called dentine. Compare cementum; enamel.

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Universalium. 2010.

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  • dentine — [ dɑ̃tin ] n. f. • 1855; de dent ♦ Anat. Ivoire des dents. ● dentine nom féminin (anglais dentine) Tissu calcifié blanchâtre qui recouvre la pulpe de la dent. dentine n. f. BIOCHIM élément constitutif de la dent, d une consistance proche de celle …   Encyclopédie Universelle

  • Dentine — Den tine (d[e^]n t[i^]n), n. [Cf. F. dentine.] (Anat.) The dense calcified substance of which teeth are largely composed. It contains less animal matter than bone, and in the teeth of man is situated beneath the enamel. [1913 Webster] …   The Collaborative International Dictionary of English

  • dentine — (US dentin) ► NOUN ▪ hard dense bony tissue forming the bulk of a tooth …   English terms dictionary

  • Dentine — La dentine appelée aussi ivoire est la substance majoritaire constituant la dent et plus généralement l organe dentaire. Elle est composée à 70 % d’hydroxyapatite, à 20 % de matières organiques et à 10 % d’eau. Elle est recouverte… …   Wikipédia en Français

  • dentine — The ivory forming the mass of the tooth. About 20% is organic matrix, mostly collagen, with some elastin and a small amount of mucopolysaccharide; the inorganic fraction (70%) is mainly hydroxyapatite, with some carbonate …   Medical dictionary

  • dentine — n. a hard tissue that forms the bulk of a tooth. The dentine of the crown is covered by enamel and that of the root by cementum. The dentine is permeated by fine tubules, which near the centre of the tooth contain cellular processes from the pulp …   The new mediacal dictionary

  • dentine — dentinas statusas T sritis chemija apibrėžtis Dantų emalio baltymas. atitikmenys: angl. dentin; dentine rus. дентин …   Chemijos terminų aiškinamasis žodynas

  • Dentine hypersensitivity — is sensation felt when the nerves inside the dentin of the teeth are exposed to the environment. The sensation can range from irritation all the way to intense, shooting pain. This sensitivity can be caused by several factors, including wear,… …   Wikipedia

  • Dentine Peak — (71°35′S 163°44′E / 71.583°S 163.733°E / 71.583; 163.733) is the highest peak (2,210 m) in the northeast portion of Molar Massif, Bowers Mountains. Named from association with Mol …   Wikipedia

  • Dentine bonding agents — Dentin bonding agents are resin materials used to make a dental composite filling material adhere to bond to both dentin and enamel. Bonding agents are often methacrylates with some volatile carrier and solvent like acetone. They also contain… …   Wikipedia

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