Advances in biocermets for bone implant applications

As two promising biomaterials for bone implants, biomedical metals have favorable mechanical properties and good machinability but lack of bioactivity; while bioceramics are known for good biocompatibility or even bioactivity but limited by their high brittleness. Biocermets, a kind of composites composing of bioceramics and biomedical metals, have been developed as an effective solution by combining their complementary advantages. This paper focused on the recently studied biocermets for bone implant applications. Concretely, biocermets were divided into ceramic-based biocermets and metal-based biocermets according to the phase percentages. Their characteristics were systematically summarized, and the fabrication methods for biocermets were reviewed and compared. Emphases were put on the interactions between bioceramics and biomedical metals, as well as the performance improvement mechanisms. More importantly, the main methods for the interfacial reinforcing were summarized, and the corresponding interfacial reinforcing mechanisms were discussed. In addition, the in vitro and in vivo biological performances of biocermets were also reviewed. Finally, future research directions were proposed on the advancement in component design, interfacial reinforcing and forming mechanisms for the fabrication of high-performance biocermets.