title: Aspects of the in vitro bioactivity of hydraulic calcium (alumino)silicate cement.
abstract: In response to a burgeoning interest in the prospective clinical applications of hydraulic calcium (alumino)silicate cements, the in vitro bioactivity and dissolution characteristics of a white Portland cement have been investigated. The formation of an apatite layer within 6 h of contact with simulated body fluid was attributed to the rapid dissolution of calcium hydroxide from the cement matrix and to the abundance of pre-existing Si--OH nucleation sites presented by the calcium silicate hydrate phase. A simple kinetic model has been used to describe the rate of apatite formation and an apparent pseudo-second-order rate constant for the removal of HPO4(2-) ions from solution has been calculated (k(2) = 5.8 x10(-4) g mg(-1) min(-1)). Aspects of the chemistry of hydraulic cements are also discussed with respect to their potential use in the remedial treatment of living tissue.
authors.affiliation: School of Science, University of Greenwich, Chatham Maritime, Kent ME44TB, United Kingdom. nj_coleman@hotmail.com
authors.forename: Nichola J
authors.initials: NJ
authors.lastname: Coleman
authors.forename: Kunle
authors.initials: K
authors.lastname: Awosanya
authors.forename: John W
authors.initials: JW
authors.lastname: Nicholson
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D000818:Animals; D001031:Apatites / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry; D001826:Body Fluids / Q000737:chemistry; D001843:Bone Cements / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008956:Models, Chemical; D012823:Silicate Cement / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; D001031:Apatites; D001672:Biocompatible Materials; D001843:Bone Cements; D012823:Silicate Cement; C049037:aluminosilicate; D002118:Calcium