Characterization of the conversion of bone cement and borate bioactive glass composites.

Borate bioactive glass 13-93B3 converts into an osteoconductive hydroxyapatite-like material in a liquid medium. In this study, 13-93B3 was incorporated into a commercial PMMA (poly(methyl methacrylate)) bone cement, and the conversion of the glass into a precipitate in solution was investigated with scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared (spectroscopy)-attenuated total reflection, and micro-Raman spectroscopy. Glass particles of 5, 33, and 100 mu m diameter were each mixed with the PMMA cement to create 20, 30, and 40% glass-loaded composites. Precipitate formation was found to be a calcium-deficient apatite partially substituted with magnesium ions that resembles native bone material and would ideally encourage bone growth better than stoichiometric hydroxyapatite. Composites of bone cement and 13-93B3 show promise as a means of encouraging bone attachment to the surface of the bone cement.