[Installation and reconstruction of autologous spongiosa and compacta after substitution with ground bone]

Defined tissue defects were made in the tibiae of 24 sheep. In each animal three defects were set; one of these was completely filled with cancellous bone and the other one with ground compact bone, whereas the third one was not grafted and served as control. During the first 3 weeks no significant difference was seen in the formation of new bone at any of the defects. Most of the ground grafts were transformed into new bone between the 4th and the 6th week; in contrast most new bone was made both in the control defect and the cancellous graft between the 7th and 12th week. In the early phase of our experiment the graft made of ground compact bone was superior to the graft formed from cancellous bone with regard to the amount of new bone formed as well as to its structure. Under clinical conditions, ground compact bone could be useful for autologous bone grafting.