In vivo investigation of biological responses to tricalcium silicate pastes in muscle tissue

The biocompatibility of tricalcium silicate (Ca₃SiO₅; C₃S) paste was studied by intramuscular implantation. C₃S paste can induce the deposition of apatite layer on its surface in the muscle tissue. The widths of apatite layer between C₃S paste and muscle tissue are increased with the increasing of implantation time. Pure C ₃S and fluorine-doped C₃S (F-C₃S) pastes induce less inflammatory reactions to the muscle tissue than PMMA paste. Pure C ₃S and F-C₃S pastes are embedded with connective tissue after 12 weeks of implantation as well as PMMA paste. However, more living fibroblasts and fewer macrophages are observed in the connective tissue around F-C₃S paste. F-C₃S paste is better biocompatibility to the muscle tissue than pure C₃S paste, because F-C₃S paste has a better deposition ability of apatite layer. Those results confirm that F-C₃S may be more biologically suitable for bone cement.