Bone induction in implants of decalcified bone and dentine.

The fate of decalcified bone and dentine implanted in muscle and beneath the kidney capsule has been studied in young rats. Quantitatively speaking there was a great deal of variation, but in general the implants became surrounded and invaded by young vascular connective tissue; then tunnels were eroded and cavities enlarged by multi-nucleated giant cells; then the matrix around erosion chambers became recalcified; and finally new bone was induced on the eroded recalcified surfaces. Erosion was much more extensive, and bone was much more readily induced in the intramuscular than in the subcapsular implants. It is concluded that the presence of an eroded, recalcified surface is a pre-requisite for bone induction under these conditions.