Silicate-doped hydroxyapatite and its promotive effect on bone mineralization

Bone defect is one of the most common diseases in clinic. Existing therapeutic approaches have encountered many problems, such as lack of autogenous allogeneic bone and immunological rejection to allogeneic implant. Synthetic hydroxyapatite (HA) provided solutions for bone repair, since the HA is the main inorganic component of animals' bone. However, HA has good biocompatibility, but does not possess osteogenic capability, which is of significance for modern bone repair materials. Si is an essential trace element in bone tissue, and it has been demonstrated to be able to promote bone formation. Therefore, silicate-doped hydroxyapatite (Si-HA) may serve as a promising material for bone repair, and promote bone regeneration in the repair. The current review discusses development of Si-HA, focusing on its preparation and characterization, in vitro and in vivo evaluations of the material, positive effect of Si-HA on promoting bone formation in clinical applications, and molecular mechanism investigation of such promotive effect.