[Bone tissue engineering for bone defect therapy].

In critical size bone defects resulting from failed fracture healing or pseudarthrosis surgery is usually required. In this context, autologous bone grafts and callus distraction represent the gold standard, while sometimes even vascularised bone transfer is mandatory including microsurgical techniques. The availability of donor sites for such procedures is limited and the resulting morbidity significant. Therefore, synthetic bone grafts have been developed as an alternative. They consist of a broad range of different materials such as natural and synthetic polymers, ceramic and compound materials, aiming to mimic the three-dimensional character of autografts. In addition, they may act as a delivery vehicle for growth factors, antibiotics or cells. Their main limitation has been the lack of an intrinsic blood supply, limiting the potential for transplantation. This review provides an overview of matrices, cells and other therapeutic substances in the field of bone tissue engineering.