Low temperature xenograft (Bio-Oss) healing.

Molar grafted with Bio-Oss 10 years prior. Patient referred for failing #13.

Bio-Oss graft site exposed.

Core sample taken from graft site shows lack of vascularity and residual bone graft granules.

Sclerotic bone with lack of vascularity and no apparent osteoblasts or osteoclasts with encased Bio-Oss granules. This specimen was demineralized and shows the residual collagen matrix in the Bio-Oss granules.

Bovine collagen matrix from demineralized Bio-Oss granule. Anorganic?

Site of extraction of tooth #3 grafted with Bio-Oss prior to implant placement. Implant in function for approximately 4 years. The graft material can be seen in the coronal portion of the extraction socket.

Patient seen on recall with graft failure. Sclerotic bone does not have the potential to remodel and adapt. The clinical of graft failure appears abrupt but the process of failure of bone grafts that produce sclerotic bone is slow. This process is covered in a following memorandum.

Biopsy of Bio-Oss graft failure. This photomicrograph shows a piece of necrotic bone removed from the site of the failed bone graft. The specimen is demineralized and stained with trichrome stain. The bulk of the specimen is comprised of sclerotic bone with encased Bio-Oss particles. Note the lack of soft connective tissue and blood vessels.

This photomicrograph is a high power resolution from the previous specimen showing sclerotic bone on the right and bovine organic matrix in the center. Blue staining of the bone matrix identifies the material as collagen.