Online Encyclopedia

Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.

HISTOLOGY

Online Encyclopedia
Originally appearing in Volume V26, Page 501 of the 1911 Encyclopedia Britannica.
» Make a correction to this article.
» Add information or comments to this article.
Spread the word: del.icio.us del.icio.us it!

HISTOLOGY . If a See also:

section he made vertically through a tooth all the exposed See also:part or See also:crown is seen to be covered with See also:enamel, which, microscopically, is composed of a number of See also:fine hexagonal prisms arranged at right angles to the See also:surface of the tooth, and formed chiefly of See also:Bone See also:Cement or Alveolar periosteum crustapetrosa or See also:root-membrane From See also:Ambrose See also:Birmingham, in See also:Cunningham's See also:Text-See also:Book of See also:Anatomy. its various parts, and its structure. See also:calcium phosphate with small amounts of calcium carbonate, See also:magnesium phosphate and calcium fluoride, but containing practically no organic See also:matter. The enamel rests on the " dentine," of which hard yet elastic substance by far the greater part of the tooth is composed. It is made of the same salts as the enamel, but contains in addition a See also:good See also:deal of organic matter and forms a structureless See also:mass through which the fine " dentinal tubes " run from the pulp cavity to the periphery. Surrounded by the dentine is the " pulp cavity," which is filled by the tooth pulp, a highly vascular and See also:nervous mass of branched connective See also:tissue cells, which, in a See also:young tooth, has a layer of See also:epithelial cells, the " odontoblasts, " lying See also:close against the See also:wall of the cavity and forming new dentine. Slender processes (" Tomes's fibrils ") project from these cells into the dentinal tubes, and are probably sensory. A See also:nerve and artery enter the See also:apex of the root of the tooth, but it is not understood how the nerve ends. Surrounding the dentine where it is not covered by enamel is the " cement " or " crusta petrosa," a thin layer of bone which is only separated from the bony socket by the alveolar periosteum.

End of Article: HISTOLOGY

Additional information and Comments

There are no comments yet for this article.
» Add information or comments to this article.
Please link directly to this article:
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML.
Site content, images, and layout Copyright © 2006 - Net Industries, worldwide.
Do not copy, download, transfer, or otherwise replicate the site content in whole or in part.

Links to articles and home page are always encouraged.

[back]
HISTIAEUS (d. 494 B.c.) 		[next]
HISTOLOGY (Gr. Ler6c, web, tissue, properly the web...

Site © 2006 - Net Industries