In vivo biocompatibility and osteogenesis of electrospun poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone)/nano-hydroxyapatite composite scaffold.

A flexible and fibrous composite scaffold composed of poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC) and 30 wt.% nano-hydroxyapatite (n-HA) was fabricated through electrospinning. In the present study, we investigated its in vitro and in vivo performance by means of hydrolytic degradation, muscle pouch implantation, as well as repair the calvarial defects in New Zealand white rabbits. The results demonstrated that the degradable scaffold held good biocompatibility. Qualitative analysis of bone regeneration process was performed by radiological examination and histological analysis. The results indicated that new bone formed originally from the margin of host bone, and then grew toward the center of defects. Moreover, the quantitative determination of newly formed bone was performed using statistical analysis of histological sections at predetermined time points. At 20th week, the defects of treatment group were covered with the new solid cortical bone. In comparison, the control group was filled with a large amount of cancelous bone and bone marrow. It suggested that the composite scaffold had better activity of guided bone regeneration than that of self-healing. So the electrospun PCEC/n-HA fibrous scaffold had the great potential application in bone tissue engineering.