"දත් දිරායාම" හි සංශෝධන අතර වෙනස්කම්
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189 පේළිය:
The structure of dentin is an arrangement of microscopic channels, called dentinal tubules, which radiate outward from the pulp chamber to the exterior cementum or enamel border.<ref name="ross450">Ross, Michael H., Gordon I. Kaye, and Wojciech Pawlina, 2003. ''Histology: a text and atlas.'' 4th edition, p. 450. ISBN 0-683-30242-6.</ref> The diameter of the dentinal tubules is largest near the pulp (about 2.5 μm) and smallest (about 900 nm) at the junction of dentin and enamel.<ref name="cate152">Cate, A.R. Ten. "''Oral Histology: development, structure, and function.''" 5th edition, 1998, p. 152. ISBN 0-8151-2952-1.</ref> The carious process continues through the dentinal tubules, which are responsible for the triangular patterns resulting from the progression of caries deep into the tooth. The tubules also allow caries to progress faster.
In response, the fluid inside the tubules bring [[immunoglobulin]]s from the [[immune system]] to fight the bacterial infection. At the same time, there is an increase of mineralization of the surrounding tubules.<ref name="summit13">Summit, James B., J. William Robbins, and Richard S. Schwartz. "Fundamentals of Operative Dentistry: A Contemporary Approach." 2nd edition. Carol Stream, Illinois, Quintessence Publishing Co, Inc, 2001, p. 13. ISBN 0-86715-382-2.</ref> This results in a constriction of the tubules, which is an attempt to slow the bacterial progression. In addition, as the acid from the bacteria demineralizes the hydroxyapatite crystals, [[
Fluids within dentinal tubules are believed to be the mechanism by which pain receptors are triggered within the pulp of the tooth.<ref>{{cite journal |author=Dababneh RH, Khouri AT, Addy M |title=Dentine hypersensitivity - an enigma? A review of terminology, mechanisms, aetiology and management |journal=Br Dent J |volume=187 |issue=11 |pages=606–11; discussion 603 |year=1999 |month=December |pmid=16163281 |doi=10.1038/sj.bdj.4800345a |url=http://www.nature.com/bdj/journal/v187/n11/full/4800345a.html}}<br/>The referred to theory is the widely-accepted hydrodynamic theory of sensitivity.</ref> Since sclerotic dentin prevents the passage of such fluids, pain that would otherwise serve as a warning of the invading bacteria may not develop at first. Consequently, dental caries may progress for a long period of time without any sensitivity of the tooth, allowing for greater loss of tooth structure.
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