Preparation And Biocompatibility Of β-Ca₂SiO₄/monetite Composite Bone Cement

Most of the bone defect caused by traumatic events, bone tumor and infection, can not be repaired by self-healing. Hence, a variety of bioactive inorganic materials have been studied and some of them have been applied as bone substitutes. Monetite cement (MC) is one of promising materials for irregular bone defect repair due to its biocompatibility, biodegradation and plasticity. Unfortunately, the inherent poor mechanical properties and low osteoinductivity of MC limited its application in clinic treatments. Therefore, β-dicalcium silicate (β-Ca2SiO4) nanoparticles were selected to reinforce the mechanical properties and enhance osteoinductivity of MC in this study.The β-Ca2SiO4 nanoparticles enhanced monetite composite cement (β-Ca2SiO4/MC), which contains different proportion of β-Ca2SiO4 nanoparticles, was successfully fabricated for further investigation. The compressive strength of the β-Ca2SiO4/MC cement containing 20%β-Ca2SiO4 nanoparticles is significantly enhanced and its average value is 18.52MPa. The plasticity of β-Ca2SiO4/MC composite cement remained despite the addition of 20%β-Ca2SiO4 nanoparticles, hence, the β-Ca2SiO4/MC composite cement containing 20%β-Ca2SiO4 nanoparticles was used as the model for further detection. The curing β-Ca2SiO4/MC composite cement induced formation of HAP layer after immersion in the simulated body fluid for 7 days, suggesting that the novel β-Ca2SiO4/MC composite cement possesses osteoinductivity in vivo.MG-63 cells, human osteoblast like cells, expanded well and displayed healthy appearance on the surface of solid β-Ca2SiO4/MC composite cement following 7 day incubation, implying that this novel β-Ca2SiO4/MC composite cement is suitable for osteoblasts growing. The transcription of FN and COL-I was significantly increased in MG-63 cells incubated with solid β-Ca2SiO4/MC composite cements compared with that incubated with cell culture plates. The transcription of BMP7, BMP4, FN and ALP was elevated in MG-63 cells after 3 days incubation by adding the material extraction solution to the culture medium. These results suggest that the β-Ca2SiO4/MC composite cement displays osteoblast induction activity and osteogenesis induction ability. In conclusion, the novel β-Ca2SiO4/MC composite bone cement exhibits high compressive strength, good osteoinductivity and plasticity, and is suitable for osteoblasts expansion.This novel β-Ca2SiO4/MC composite bone cement can be applied for linic usage in the future.