Development of a composite based on hydroxyapatite and magnesium and zinc-containing sol-gel-derived bioactive glass for bone substitute applications

In the present study, a bioceramic-based composite was prepared by sintering compacts made up of mixtures of hydroxyapatite (HA) and sol-gel-derived bioactive glass (64SiO(2)-26CaO-5MgO-5ZnO) (based on mol%) powders. HA powder was mixed with different concentrations of the glass powders up to 30 wt.%. The effect of adding bioactive glass powder to HA matrix, on the mechanical properties of the composite was assessed by compression test. The specimen with the highest compressive strength was chosen to be immersed in simulated body fluid (SBF) to study apatite forming ability and dissolution behavior. It was found that compressive strength of the specimen was decreased 65% after maintaining in the SBF for 14 days. X-ray diffraction (XRD) showed prevalence of HA and beta-TCP related peaks. Also, the surface morphology of the composite was observed using scanning electron microscopy (SEM). The study of degradation behavior revealed Si release capability of this composite. Biological evaluations in vitro confirmed the composite studied could induce osteoblast-like cells' activities. (C) 2012 Elsevier B.V. All rights reserved.