Synthesis and characterization of multiphase bioactive glass-ceramics in the CaO-MgO-SO2 system with B2O3 additive

A glass-ceramic (GC0) with nominal composition of 51.2% CaO-12.1% MgO-36.7% SiO2 (wt%) was synthesized. Then multiphase glass-ceramics of MGC1 and MGC2 were obtained by adding 1 and 2 wt% B2O3 to GC0 followed by thermal treatment. The bending, strength of MGC1 was the highest, about 89.46 MPa, and the coefficient of thermal expansion was 10.67 x 10(-6) degrees C-1, closer to that of Ti-6A1-4V alloy (10.03 x 10(-6) degrees C-1). X-ray diffraction analysis confirmed that MGC1 was predominantly composed of akermanite, merwinite, and small amounts of dicalcium silicate crystalline phases. The bioactivity and cytocompatibility in vitro of MGC1 were detected by investigating the bonelike apatite-formation ability in simulated body fluid (SBF) and osteoblast morphology and viability. The results showed that MGC1 possessed bonelike apatite-fori-nation ability in SBF and Could release ionic products to significantly stimulate cell growth and viability. Furthermore, osteoblasts adhered and spread well on MGC1, indicating good bioactivity and potential cytocompatibility.