Abstract
Recycling unnecessary teeth for use as a bone grafting material should be a valuable approach to enhance the bone-forming process in alveolar bone defects and to reduce material costs. However, the process of bone formation using grafting material is not fully understood. The aim of this study was to assess the fate of material including milled teeth by immunohistological observation in a rat incisor extractionmodel. Freeze-milled incisor material was injected into an extraction socket in a rat mandible bone. Four weeks after the operation, the mandible was sampled and frozen sections were prepared by the sticking film method, after which DMP-1 and CD68 were visualized by immunohistochemical staining. The results revealed that milled tooth particles remained around the socket at four weeks post-operation, and showed different reactions depending on the particle size. Small particles (3-10 μm) were phagocytosed by CD68-positive cells, whereas bone regeneration occurred around large (30-60 μm) particles. These results suggest that the injection of crushed teeth could provide an optimum scaffold and growth factors for bone formation in extraction sockets.
