Use of demineralized allogeneic bone implants for the correction of maxillocraniofacial deformities

Two major problems in maxillocraniofacial surgery are the limited amount of fresh autogenous bone, the standard material for bone grafting, and the resorption of the grafted bone. Experimental studies with demineralized, devitalized bone matrix have shown induction of endochondral ossification. Fifty-five demineralized allogeneic implants have been used in 44 patients over the past two years for a variety of congenital (n = 37) and acquired (n = 7) defects. The allogeneic bone was obtained from cadavers, prepared as powders, chips or blocks, and was demineralized. After having been sterilized by irradiation, they were used to augment contour, fill defects, or construct bone within soft tissue. Of implanted sites that could be evaluated by physical examination, 31 of 31 were solid by three months. By radiographic examination three of 19 were healed by three months, and an additional 11 were positive by six months. Induced bone was seen in four of four biopsy specimens. Infection occurred in four of 44 patients (9%), comparable with conventional grafts. Implant resorption occurred in four instances. Allogeneic demineralized implants offer several advantages over conventional bone grafting, such as avoidance of a harvesting operation, ease of manipulation, and potentially unlimited material in banked form. In addition, healing by induced osteogenesis may bypass the resorption seen with healing of mineral-containing grafts.