Synthesis and characterization of novel multiphase bioactive glass-ceramics in the CaO-MgO-SiO(2) system

Three new chemical compositions based on the CaO-MgO-SiO(2) system were designed first, and then three novel glass-ceramics (M1, M2, and M3) were prepared by sol-gel method. X-ray diffraction analysis confirmed that they were predominantly composed of akermanite, wollastonite, and dicalcium silicate crystalline phases. The coefficient of thermal expansion (CTE) of M2 was 10.79 x 10(-6) degrees C(-1), closest to that of Ti-6Al-4V alloy, and the Young's modulus of M2 was 29.73 GPa, similar to that of the cortical bone. The bioactivity in vitro of M2 was evaluated by investigating its bonelike hydroxyapatite (HA)-formation ability in simulated body fluid (SBF), and the biocompatibility in vitro was detected by osteoblast proliferation, differentiation, and adhesion assay. The results revealed that M2 possessed bonelike carbonated hydroxyapatite (CHA)-formation ability in SBF and could significantly stimulate cell proliferation and differentiation. Furthermore, osteoblasts adhered and spread well on M2, indicating good bioactivity and biocompatibility in vitro.