Electron microscopy of induced heterotopic bone formation in guinea pigs

Abstract

A high yield of osteoid and some mineralized bone was induced in the abdominal muscles following implantation of allogenic demineralised and lyophilized dentine. The following types of cells and reactions were found: A. Resorptive reaction mediated by monocytes, macrophages and dentinoclasts. B. Fibroblastic reaction, as an unspecific capsulation process. C. Osteoblastic reaction with osteoid formation. Dentinoclasts were observed before remineralisation of the implanted dentine. Macrophages were active in the resorption of dentine, especially in the earliest stages. In dentinoclasts near remineralized dentine, crystals were observed in the ruffled border. Channels to the surface were found in osteoblasts, possibly originating from endoplasmic reticulum.