Biodegradation of porous alpha-tricalcium phosphate coated with silk sericin

Porous α-tricalcium phosphate (α-TCP) ceramics are attractive as a novel bioresorbable material for bone repair, since they can be easily fabricated through conventional sintering of ß-TCP at high temperature. However, the solubility of α-TCP is too high to keep its body until the bone defect is repaired completely. Coating of the α-TCP porous body with organic polymer is a way to reduce the degradation rate. In the present study, biodegradation of α-TCP porous body coated with silk scricin was evaluated in vivo. Bone repair at the defect made in rabbit tibia was nearly completed after 4 weeks. Higher density of cortical bone was estimated for α-TCP coated with sericin than for mere α-TCP. The α-TCP porous body coated with sericin is expected as a material that show less degradation than mere α-TCP, and may result in suitable bone repair.