Abstract: The invention is directed toward a sterile bone structure for application to a bone defect site to promote new bone growth at the site comprising a partially demineralized cortical bone structure, said bone structure comprising a cross sectional surface are ranging from 85% to 95% of the original bone surface area before demineralization with the remaining partially demineralized cortical bone structure having an outer demineralized layer ranging in thickness from about 0.05 mm to about 0.14 mm and a mineralized core.