In present study for evaluation of bone induction and processing of new bone regeneration in cranial bone, we implanted BMG particles in the rat parietal bone defects. The BMG was prepared as previously described by urist. The defects with 5-mm in diameter were produced in left parietal bones and filled by 5-mg of BMG particles. No BMG particles used in control group.
For evaluation of new bone induction and regeneration, speciements were harvested on days 3, 5, 7, 10, 14, 21 and 28 after implantation. The samples were processed histologically, stained by H&E, Alcian blue and Alizarin red S and studied by using a light microscope.
The results are as fallows: In control group: Twenty-eight days after operation a few clusters of new bone were observed near the defects margin. In BMG group: The first cells that differentiated from the mesenchymal cells, were osteoblasts that appeared 3 days after implantation, followed by synthesis of bone matrix which classified shortly thereafter. A few clusters of cartilage cells were observed at beginning of day 7 which located in the central position of the defects. By 14th days after implantation, Alcian blue staining showed hypertrophic chondrocytes and classified deposition were detectable by alizarin red S staining. The new trabeculae bone was observed in peripheral position and near the defects margin in this day. The numerous trabeculae bone with adult osteocytes and red bone marrow well developed on day 21 after implantation. Finally typical lamellar bone with regulated osteocytes, osteoblast cells and some osteoclast cells' were detectable in day 28 after implantation.
In Conclusion, the BMG could stimulated bone induction and new bone regeneration by ordinary both ossification methods "Preferely intramembranous ossification" in cranial bone defects. So it seems that the BMG could be good biomaterial substances for bone repair.