HA forming ability of some glass-ceramics of the CaMgSi2O6-Ca5(PO4)3F-CaAl2SiO6 system

A new bioglass-ceramics based on various content of the diopside [CaMgSi2O6]-fluorapatite [Ca-5(PO4)(3)F]-Ca-Tschermak's [CaAl2SiO6] system with minor additives of (Na2O, B2O3 and TiO2) were formulated. The surface reactivity of the glass-ceramic specimens was studied in vitro in Kokubo's simulated body fluid (SBF). EDAX-SEM, and inductively coupled plasma (ICP) emission spectroscopy were used to characterize the glass-ceramic surfaces and the SBF compositional changes. Different bioactivity behaviour could be detected. Some samples showed a high reactivity with the (SBF) solution forming apatite rich layer on their Surfaces as indicated from the EDAX-SEM and (ICP) data. However, other samples, which contain high percentage of Ca-Tschermak's component, i.e. rich in Al2O3, showed minimum presence or absence of apatite layer, which indicated that moderate or inert bioactive materials were also formed. The prepared glass-ceramics had hardness, 6925-8055 MPa, thermal expansion coefficients in the 25-700 degrees C temperature range, 72 x 10(-7) to 105 x 10(-7) degrees C-1 and density values in the range, 2.78-2.94 g/cm(3). (C) 2005 Elsevier Ltd and Techna Group S.r.l.. All rights reserved.