Osseous-plastic material «Perfoost» - demineralized lyophilized perforated allografs- was elaborated at CITO in 1997. Study of mechanical characteristics showed that «Perfoost» grafts had high plasticity. Mechanical stiffness allowed to use that material for substitution of marginal bone defects. Study in vitro showed high efficacy of cloning that was indirect evidence that demineralized allografts had osteoinductive properties. Between 1998-2002 at the Department of bone pathology for children and adolescents 121 patients, aged 1-18, with primary tumor, tumor-like diseases and systemic inherited skeleton pathology were operated on with «Perfoost». Follow up period ranged from 1 years to 4 years 10 months. In vast bone defects demineralized allografts were used in combination with frozen cortical implants and metallosteosynthesis. Restoration of bone tissue was achieved in the period from 8 to 12 months. In patients with fibrous dysplasia who underwent extensive bone resection, the time of bone restoration increased by 16 months. Good and satisfactory results were observed in 98,3% of patients.