Objectives:Loss of bone substance is a major source of disabiltiythat often requires grafting.Recentlydeveloped synthetic bone grafts have generated a lot of enthusiasm due to the lack of immunological reactions and infectious disease transmission risk. The current work describes some peculiar complications related to the use of calcium sulfate granules. Methods: 15 implantations of calcium sulfate pellets Osteoset (Wright Medical Technology) were performed following resection of bone tumors at our service during 1999. Clinical or computerized tomography scans were available in all patients. Results: 3 cases were encountered in which a severe inflammatory reaction developed. In one case serous drainage and an allergic reaction obligated graft removal. In another case, inflammation resolved two months following implantation. In the last case, wound breakdown occurred. Conclusions: A sterile inflammatory response has previously hindered the use of absorbable poly-lactic and poly-glycolic acid rods. Apparently due to rapid graft resorption, the resulting calcium-rich fluid incites inflammation. The single case of an allergic reaction is interesting. An allergy to plaster of Paris is rare and related to minor additives. These were not present in the bone substitute used. Inflammatory complications should be considered when assessing the risk-benefit ratio of using different types of bone replacement materials, and comparing allogeneic grafts to synthetic ones.

Keywords: synthetic bone substitutes, bone graft, Calcium Sulfate