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[si-men-tuh m] /sɪˈmɛn təm/
noun, Dentistry.
the bonelike tissue that forms the outer surface of the root of the tooth.
1605-15; < Latin, variant of caementum rough stone; see cement Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for cementum
  • cementum, which can be thick in extinct genera, covers the outside of the tusk.
  • It consists of the cementum, periodontal ligaments, alveolar bone, and gingiva.
  • Of these, cementum is the only one that is a part of a tooth.
British Dictionary definitions for cementum


a thin bonelike tissue that covers the dentine in the root of a tooth
Word Origin
C19: New Latin, from Latin: cement
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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cementum in Medicine

cementum ce·men·tum (sĭ-měn'təm)
A bonelike substance covering the root of a tooth. Also called cement.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Article for cementum

in anatomy, thin layer of bonelike material covering the roots and sometimes other parts of the teeth of mammals. Cementum is yellowish and softer than either dentine or enamel. It is made by a layer of cementum-producing cells (cementoblasts) adjacent to the dentine. The fibres of the periodontal membrane, which holds the tooth in its socket, are embedded in the cementum. Deposition of cementum continues throughout the life of the animal, especially in response to stresses. In humans, for example, as the tooth crown wears down, new cementum is deposited on the roots so that the tooth gradually rises higher in the socket and good occlusion (bite) is maintained.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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