In vitro bioactivity of glass–ceramics of the CaMgSi 2O 6–CaSiO 3–Ca 5(PO 4) 3F–Na 2SiO 3 system with TiO 2 or ZnO additives

Abstract

Glass–ceramic materials based on diopside [CaMgSi 2O 6]–wollastonite [CaSiO 3]–fluoroapatite [Ca 5(PO 4) 3F]–sodium silicate [Na 2SiO 3] system with TiO 2 or ZnO additives were successfully prepared and examined in vitro, by using a simulated body fluid (SBF) solution, to be suitable for restorative dental and bone implant materials. In vitro bioactivity of the glass–ceramics was examined by using scanning electron microscopy equipped with energy dispersive X-ray detectors (EDAX–SEM) and inductive coupled plasma emission spectroscopy (ICP). The addition of TiO 2 showed a great positive effect on the bioactivity behaviour of the crystallized sample, while introducing ZnO to the glass led to decrease the rate of apatite formation on the corresponding glass–ceramic sample. In vitro test of glass–ceramics containing sodium calcium silicate solid solution showed higher bioactivity than that containing fluoroapatite. This fact indicated that the sodium calcium silicate solid solution has higher bioactive index than fluoroapatite. The coefficients of thermal expansion of the obtained glass–ceramic materials are between 97 × 10 −7 K −1 and 127 × 10 −7 K −1 in the 25–600 °C temperature range and the Vicker's microhardness values are between 4635 MPa and 6615 MPa.