Xenogenic demineralized bone matrix: osteoinduction and influence of associated skeletal defects in heterotopic bone formation in rats.

Demineralized bone matrix (DBM) was ectopically implanted in 36 male Wistar rats. In 18 of the animals a bone defect in the femoral condyles was also created: the left was filled with DBM and the right was left empty as a control. The animals were killed after 2, 4 and 6 weeks and new bone was histologically evaluated, comparing ectopic bone formation with or without distant bone injury. Results showed: (1) osteoinductivity of xenogenic DBM, and (2) earlier mineralization of ectopically implanted DBM in the group with associated skeletal injury. Our results show that xenogenic bone matrix acts as an osteoinductive material and that skeletal injury improves osteogenesis at distant sites.