ABSTRACT
BACKGROUND: Dentin particles, tricalcium phosphate/collagen protein composites and Bio-oss particles can repair jaw defects, but the excellent osteogenic effect is not clear. OBJECTIVE: To compare osteogenic effects of three different bone graft materials on mandibular defects in beagle dogs. METHODS: Eight 1-year-old beagles were selected. A boxed bone defect area of 10 mm × 8 mm × 2 mm was prepared at the bilateral mandibular external oblique line and randomly divided into four groups with four bone defect models in each group. Undemineralized dentin particles were implanted in group A; tricalcium phosphate/ collagen protein composite materials were implanted in group B; Bio-oss particles were implanted in group C; and group D was used as blank control. Three months after transplantation, the samples were taken for histological observation. The experimental animals were approved by the Ethics Committee of the Experimental Animal Center of Dalian Medical University. RESULTS AND CONCLUSION: (1) In group A, dentin particles were slightly absorbed, surrounded by new bone tissue; new bone trabeculae and capillaries could be seen, and a large number of fibrous connective tissue surrounded dentin particles in the central area of bone graft. In group B, a small number of new bone trabeculae and osteoblasts could be seen; a large number of powdered β-tricalcium phosphate particles and a small amount of inflammatory cells could be seen in the fibrous connective tissue; and some β-tricalcium phosphate particles were surrounded by new bone tissue. Bone marrow cavity could be seen in the new bone. In group C, some Bio-oss particles were surrounded by new bone tissue; some Bio-oss particles were wrapped by surrounding fibrous connective tissue, and fibers, particles and new bone were intertwined. There was no new bone formation in group D, and many capillaries could be seen in a large number of fibrous connective tissue. (2) The rate of new bone formation in groups A, B and C was higher than that in group D (P < 0.05); the rate in groups A and C was higher than that in group B (P < 0.05). (3) The results show that all the three kinds of bone graft materials can promote the formation of new bone. The short-term osteogenic effects of undecalcified xenogeneic dentin particles and Bio-oss particles are better than tricalcium phosphate/collagen protein composites, but the long-term effects need to be further observed.