Hard, bone-like projections set in the jaws and surrounded by the gums. The teeth are used for mastication, help to form speech, and give shape to the face. At the centre of each tooth is the pulp, which contains blood vessels and nerves and is surrounded by hard dentine. The part of the tooth above the gum, the crown, is covered by enamel, the hardest substance in the body. The roots of the tooth, which fit into the jawbone, are covered by bone-like cementum. Humans have 32 permanent teeth, which erupt after the primary teeth are lost. These teeth comprise chisel-shaped, biting incisors; sharp, pointed canines; grinding premolars; and larger grinding molars.
Teeth |
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