USE OF OSTEOINDUCTIVE IMPLANTS IN THE TREATMENT OF BONE DEFECTS

Osteogenic proteins (OPs) are a family of bone matrix polypeptides iso lated from a variety of mammalian species, including mouse, rat, bovin e, monkey, and man. OPs initiate chondroblastic differentiation in plu ripotent mesenchymal progenitor cells, followed by the synthesis of ne w bone by endochondral ossification. OPs have the ability to induce he aling of osteoperiosteal defects in several animal models, supporting a possible therapeutic role in the reconstruction of bone defects. OPs are responsible for the osteoinductive capacity of demineralized bone matrix (DBM) implants, which may also prove to be clinically useful. Preliminary studies using purified, naturally occurring human osteogen ic proteins in the clinical management of non-unions have reported pro mising results. A prospective, randomized clinical trial is currently underway, comparing recombinant human osteogenic protein-1 (rhOP-1) to autograft in the treatment of tibial non-unions. The use of osteogeni c protein implants to augment or replace autogenous and allogenous bon e grafts will reduce morbidity, and circumvent the risk of disease tra nsmission associated with transplantation.