Bone tissue engineering has been paid much attentions because millions of patients undergo bone diseases globally while the traditional treatments of bone grafts and graft substitutes were faced with some disadvantages, including complicated surgical procedures, chronic inflammation, immune rejection, etc. The fabrication of ideal scaffold providing a suitable site for cell adhesion, proliferation and differentiation is still a major challenge. Hydroxyapatite (HA) is recognized as a preferable material for bone tissue engineering because its chemical composition is similar to the inorganic part of natural bone, and HA possessed excellent biocompatibility, bioactivity and osteoconductivity. But the poor degradability of HAP limits its application due to the impediment to prevent new bone from growing into the implant scaffolds.
Zhong et al. from Zhejiang Sci-Tech University introduced a novel injectable and degradable hydroxyapatite-based bone repair material. CaCO3 regulated by silk sericin was utilized as a template to prepare porous CaCO3/hydroxyapatite composite microspheres throughhydrothermal treatment. In vitro and in vivo degradation behaviors of CaCO3 and hydroxyapatite microspheres were evaluated. The results indicated that the degradation pattern of the composite microspheres could be changed by adjusting the reaction time of hydrothermal treatment to match the growth speed of new bone and the composite materials showed an improved cytocompatibility, which might be a promising biomaterial for bone repair.