BackgroundAmong orthopedic surgery materials, poly (methyl methacrylate) (PMMA) is most commonly used for its excellent mechanical properties and rapid self-setting time. However, PMMA bone cement has been reported to cause thermal necrosis and to have poor bioactivity, which must be improved. In contrast, tricalcium silicate (TCS), the most significant component of Portland Cement and the most effective bone cement material, might not always meet the needs of the cement due to its poor mechanical properties and elevated pH levels during hydration. We hypothesize that the benefits of both PMMA and TCS can be harnessed by mixing them together in different proportions. This would represent a better solution for the issues faced when using them alone.MethodsWe, therefore, prepared a novel organic-inorganic PMMA/TCS composite bone cement mixing PMMA and different amounts of TCS and tested its effect on the biophysical properties.ResultsThe addition of 30% TCS reduced the exothermic temperature and pH variation during cement setting and hydration processes. However, the mechanical and handling properties of the bioactive PMMA/TCS composite were not affected. Thein vitrostudy also revealed that the composite materials had higher cell viability than pure PMMA and TCS. Also, thein vivostudy on animals indicated that the composite materials were more capable of forming bone, which further reinforced the biocompatibility of the proposed PMMA/TCS bone cement.ConclusionBy combining the advantages of each component, it could be possible to construct a more effective composite bone cement material. This would meet the needs of implantation material for orthopedic surgeries or a possible bone filler.