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Structures of Biological Minerals in Dental Research



M Mathew, Shozo Takagi


Structural features of some calcium phosphates of biological interest are described. Structure of hydroxyapatite (OHAp), considered as the prototype for the inorganic component of bones and teeth is discussed with respect to the kinds and locations of ionic substitutions. Octacalcium phosphate (OCP), is a probable precursor in biological mineralization. OCP has a layer type structure, with one layer quite similar to that of OHAp and the other, a hydrated layer consisting of more widely spaced Ca, and PO4 ions and the water molecules. The closeness of fit in the apatitic layers of OCP and OHAp accounts for the epitaxial, interlayered mixtures formed by these compounds and the in situ conversion of OCP to OHAp. Possible roles of OCP in biological mineralization are discussed.
Journal of Research (NIST JRES) -
106 No. 6


biominerals, calcium phosphates, crystal structure, fluorapatite, glaserite, hydroxyapatite, octacalcium phosphate


Mathew, M. and Takagi, S. (2001), Structures of Biological Minerals in Dental Research, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 28, 2024)


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Created December 1, 2001, Updated February 17, 2017