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 C3S and fluorine-doped C3S (F-C3S) pastes induce less inflammatory reactions to the muscle tissue than PMMA paste. Pure C3S 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.