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Crystal chemistry and dissolution of calcium phosphate in dental enamel

Published online by Cambridge University Press:  05 July 2018

S. E. P. Dowker
Affiliation:
Dental School, St Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary and Westfield College, Turner Street, London E1 2AD, UK
P. Anderson
Affiliation:
Dental School, St Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary and Westfield College, Turner Street, London E1 2AD, UK
J. C. Elliott
Affiliation:
Dental School, St Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary and Westfield College, Turner Street, London E1 2AD, UK
X. J. Gao
Affiliation:
Department of Endodontics, School of Stomatology, Beijing Medical University, Haidian, Beijing 100081, PR China

Abstract

The mineral component (at least 95 wt. %) of dental enamel is hydroxyapatite (hydroxylapatite) with multiple substitutions. The biogenic origin of enamel is reflected in the unusual ribbon-like morphology of the crystals, which are extremely elongated in the c-axis direction, and their organized arrangement within the tissue. The study of enamel dissolution has been driven by the very high prevalence of dental caries. In enamel caries, the initial demineralization results in subsurface dissolution of mineral. While the surface remains intact, reversal of the lesion by remineralization is possible. Problems of understanding the physico-chemical processes in enamel demineralization include the general problems concerning the structure and chemistry of apatites formed in aqueous media. Added to these are the general problem of dissolution in an inhomogeneous porous medium and the complication that enamel apatite has a naturally variable composition which changes during demineralization. The use of model systems in caries research is illustrated by reference to X-ray absorption studies of enamel and synthetic analogues.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1999

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