In Vitro and In Vivo Assays of Cartilage Repair by Perforated Polyurethane Scaffold

Synthetic polymeric systems are considered vitally important in tissue regeneration.The reasons lay behind their specific characteristics such as porosity,hydrophilicity, degradation time, and mechanical properties which are variable toa large extent. The segmented polyurethanes have been used as biomaterials inmedical field because they possess unique properties. In this study, the perforatedpolyurethane (PPU) scaffold as cartilage substitution was prepared and evaluatedthrough biological assays. During the in vitro stage, the behaviour of both primarychondrocyte cells and L929 cell line in presence of PPU were examined. To evaluatein vivo performance of the scaffolds, PPUs were implanted in the scapula cartilage oftwelve mixed-bred female sheep and comparisons were made with the implantedautologous cartilages as control. The results of in vitro studies showed some round andaggregated chondrocyte cells grown after 2 weeks of cell culture along with aconsiderable growth and attachment of L929 cells. In vivo studies showed that there isno significant difference between the restored PPUs and the autologous cartilagecontrol. Our studies support the potential use of PPU as a proper substitute or ratheras an assistant in cartilage repair. Obviously, further studies are needed to qualify theconstituted cartilages regarding proteoglycan and collagen productions.