Tissue response to bioactive glass and autogenous bone in the rabbit spine.

Bioactive glass S53P4 and autogenous bone were used as bone graft materials in an experimental rabbit model for spinal fusion. The study focused on differences in bone formation using bioactive glass and autogenous bone as bone graft materials. Bioactive glass, a mixture of bioactive glass and autogenous bone or autogenous bone was implanted for 4 and 12 weeks at the thoracolumbar level. Undecalcified sections were prepared for histological and histomorphometric evaluation. New bone formation was seen in all implanted areas, with the bone growing from the surface of the vertebrae enclosing both glass and autogenous bone in the bone fusion mass. During the observation period, the measured amount of bone remained at the same level in the autograft group, while in the glass and the glass/autograft bone groups it increased. By 12 weeks, no significant difference in bone formation between the three groups was observable. The bone formation in two selected standardized areas at 12 weeks was 21 and 24% in the glass group, 23 and 28% in the glass/autograft bone group and 27 and 26% in the autograft bone group. We consider bioactive glass as a potential bone graft material in experimental spinal fusion.