A 6-month in vivo study of polymer/mesenchymal stem cell constructs for cranial defects

Two biodegradable polymers, poly(L-lactide) and poly(epsilon-caprolactone) were blended (50/50) and used to produce polymeric scaffolds by the dual porogen approach using a salt leaching technique to create pores within the matrix, while supercritical-CO2 treatment was used to enhance the interconnectivity and to remove impurities from synthesis steps. The scaffolds were highly porous (porosity >90%) with interconnected pore morphologies. These biodegradable scaffolds were evaluated in Sprague Dawley rats for osteoconductive properties over a 6-month period. Bone specimens were analyzed after 1, 3, and 6 months, for bone healing and tissue response. The cortical bone remodeling by controlled osteoblastic and osteoclastic activities as well as the bone marrow elements recovery were semi-quantitatively examined for each group. Excellent integration and biocompatibility behavior was observed in all groups. No adverse tissue responses were observed