Particulate aluminum oxide as a bone graft material.

The performance of particulate aluminum oxide (Al2O3) as a bone graft material was evaluated by comparison to two other graft materials, autogenous bone and particulate hydroxylapatite (HA). Holes were drilled through the medial cortex of both the distal femora and proximal tibiae in three dogs. The Al2O3, HA and autogenous bone were packed into the created defects and the rate and extent of defect healing examined. Particulate Al2O3 and HA were also placed on opposite sides of the median sacral crest in a spinal fusion procedure. One dog was sacrificed at 4, 8 and 12 weeks post-operative. The extent and rate of healing was superior with the autogenous bone, while the performance of the HA was superior to that of the Al2O3 at 4 and 8 weeks. However by 12 weeks, the performance of the two non-autogenous materials was equivalent. At 12 weeks the majority of the cancellous defect was infiltrated with viable bone with all three materials. In the spinal fusions, results were not as encouraging, with less bone present within the graft materials as compared to the cancellous defect implantations.