The Hydroxyapatite / Drynaria The Composite Materials To Repair Bone Defects In Rabbits

OBJECTIVE: To investigate and evaluate the biocompatibility,osteogenesis and effect of repairing bone defect of Natural hydroxyapatite/Drynariae Rhizoma (HA-DR) that implanted in the rabbit jaw defect by X-ray, optical microscope and Scanning electric microscope .In order to offer the experiment base of treating the bone defect and the theory foundation of clinic application.METHODS: Drynaria powder to 10% of the total by adding the proportion of hydroxyapatite powder, are mixed fully prepared Hydroxyapatite/Drynaria composite materials. Natural hydroxyapatite group and synthetic hydroxyapatite group were used as the controls. The implant materials were to join the 5:1 ratio of dispersant dextrin in order to increase the strength and toughness of implant materials. Thirty -six Harbin healthy adult rabbits'bilateral mandibular body were used to form 1.0cm×1.0cm×0.3cm of the artificial bone defect, where is implanted artificial bone defect materials. In batches week after 4, 8, 12 ,16 animals were killed. Gross Anatomy, X-ray, Histology, Scanning electron microscopy to observe, in general anatomy specimens to observe the situation of repairing bone defect and with the combination between the materials and surrounding tissue; X-ray film taken the procedures of deal with image to analysis of density; ordinary optical microscope to observe changes in histology and the new bone growth; scanning electron microscope to observe the situation of materials combined with bone and new bone growth.RESULTS: The hydroxyapatite/Drynaria composite materials, as well as natural hydroxyapatite, synthetic hydroxyapatite have good biocompatibility, which were implanted in animals no infection and rejection. Hydroxyapatite/Drynaria composite group in the density measurements, 4 weeks, 8 weeks, 12 weeks, 16 weeks to repair defect density areas gradually reduced, there is significant difference (P <0.01). Histological observation, 4 weeks with between the bone and material were a large number of fiber and the formation of osteoblasts, and a small amount of new bone formation. 8 weeks with bone material at the junction of a large number of new bone formation, but is not yet mature, and a small amount of absorption material; 12 weeks when the new bone more mature, lamellar structure clearly and shows that harvard's system, materials and bone has a fuzzy interface. 16 weeks when a large number of new bone formation, trabecular bone neatly arranged, bone remodeling basically completed, the basic material was completely absorbed. SEM confirmed that the new bone was a gradual process of maturation. In histology, X-ray and scanning electron microscope showed that hydroxyapatite/Drynaria composite group to repair bone defects than the degree of synthetic hydroxyapatite group is superior to natural hydroxyapatite group .CONCLUSION: Hydroxyapatite/Drynaria composite materials significantly promote the repair of bone defects, is stronger than synthetic hydroxyapatite and natural hydroxyapatite. Guided bone and bone induction comprise Osteoblasts form. The synergy between them can be used to repair bone defects.