Role of acid attack in the in vitro bioactivity of a glass-ceramic of the 3CaO.P2O5-CaO.SiO2-CaO.MgO.2SiO2 system.
A non-bioactive glass-ceramic (GC13) that contains hydroxyapatite (Ca5(PO4)3OH), diopside (CaMg(SiO3)2) and althausite (Mg2 PO4OH) as crystalline phases has been obtained by thermal treatment of a parent bioactive glass (G13) of nominal composition (wt%) 40.0 CaO-34.5 SiO2-16.5 P2O5-8.5 MgO-0.5CaF2. To induce bioactivity, GC13 was chemically treated with 1 M HCl for different periods of time. After chemical etching the in vitro studies showed formation of an apatite-like surface layer. In this article the influence of etching time both on the surface composition of the glass-ceramic and on the growth rate of the apatite layer is studied. It is concluded that the presence of hydroxyapatite in the glass-ceramic, associated to microstructural fluctuations, can favour apatite deposition in vitro.
Roman
J
J
Department of Quimica Inorganica y Bioinorganica, Facultad de Farmacia, Universidad Complutense de Madrid, Spain.
Salinas
A J
AJ
Vallet-Regi
M
M
Oliveira
J M
JM
Correia
R N
RN
Fernandes
M H
MH
D001031:Apatites / Q000032:analysis*; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D002118:Calcium / Q000032:analysis; D002516:Ceramics / Q000737:chemistry* / Q000494:pharmacology; D003460:Crystallization; D017886:Durapatite / Q000737:chemistry* / Q000494:pharmacology; D006851:Hydrochloric Acid / Q000494:pharmacology*; D008274:Magnesium / Q000032:analysis; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010758:Phosphorus / Q000032:analysis; D012825:Silicon / Q000032:analysis; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
D001031:Apatites; D001672:Biocompatible Materials; C439610:GC13 ceramic; D010758:Phosphorus; C023506:Glass ceramics; D017886:Durapatite; D008274:Magnesium; D006851:Hydrochloric Acid; D002118:Calcium; D012825:Silicon