Calcium phosphate ceramics as substrate for cartilage cultivation

Hip, knee and shoulder joints are complex structures that bear a combination of articular cartilage, bone and synovial fluid. Articular cartilage is a shock-absorbing tough, connective tissue that covers the ends of bones in joints and enables the bones to glide over one another. Since there are no nerves or blood vessels in cartilage, once it is damaged it has a reduced ability to repair or restore itself. Thus, there has been continuous research on the regeneration of cartilage by tissue engineering. Our investigation is focussed on a tissue engineered cartilage-carrier-construct, where the cartilage is grown on top of a ceramic carrier as bone equivalent. Calcium phosphates are widely used as bioceramics due to their biocompatibility and bioactivity. Former in vivo (mini pig) investigations have demonstrated the potential of this concept for local cartilage repair. But still the properties of the carrier have to be optimised. In this study different types of calcium phosphate ceramics with different surface properties were investigated in order to generate cartilage on their surfaces. The results indicate that the adhesion of cartilage/calcium phosphate is a critical parameter for reliable implants.