Bovine bone implant with bovine bone morphogenetic protein in healing a canine ulnar defect

Xenograft is considered an alternative material for bone transplantation, b ut its bone healing capacity is inferior compared to that of autografts and allografts. Here, we tested whether bone morphogenetic protein (BMP) addit ion enhances the suitability of demineralized xenogeneic bovine bone for bo ne grafting in dogs, and whether xenogeneic bone is a suitable carrier mate rial for BMPs. The capacity of demineralized bovine bone implants, with and without native partially purified bovine BMP, to heal a 2-cm ulnar defect was determined in six dogs over a follow-up time of 20 weeks. No instances of bone union were seen, but there was slightly more bone formation in the xenografts with BMP, though the difference was not statistically significan t. The ulnas treated with an implant with BMP were also mechanically strong er, but the difference was not significant. Computed tomography scans showe d no differences in the implant area in bone density, bone mineral content, or bone cross-sectional area. It is concluded that native, partially purif ied BMP does not sufficiently improve the suitability of bovine demineraliz ed xenografts as a bone substitute material for dog. Demineralized xenogene ic bone does not seem to be a feasible carrier material for BMP.