Study on the construct and properties of polyurethane cartilage and bone bilayered composite

Damage to articular cartilage is one of the most common diseases in clinic,and may lead to the development of osteoarthritis because this tissue has poor regenerative capacity.Therefore,exploring a suitable osteochondral substitute transplanting graft is of great importance.The aim of the present work was to make a bilayered construct by integrating a tissue-engineered cartilage into an underlying bony substrate in order to solve the integration problem of cartilage and subchondral bone.The cartilage material was polyurethane and the underlying bony substrate was hydroxyapatite/polyurethane composite scaffold,and the same material,that is polyurethane,used in both structures integrated two layers together and made the conglutination more firmly.The subchondral part of the bilayered construct had an interconnected porous structure with a porosity of 83% and pore size ranging from 200μm to 600μm.In vitro biocompatibility tests showed that the incorporated bilayered construct provided a favorable environment for initial cell adhesion,and maintained cell viability and cell proliferation.The results suggest that the bilayer material has the potential for further application in osteochondral tissue engineering.