Abstract:

Objective:Sr-HA, a newtype of hydroxyapatite biomaterial, was implanted into animals to study the bioreaction and charac- ter, which would be helpful for the further clinical applications in the future.Methods:Totally 24 rabbits were divided into 3 groups. The bone defectof 6 mm@12 mm@4 mmwasmade atbothmandibular angles of rabbits and Sr-HAof differentproportion (10%, 5%, 0) was applied to reform the defects. One group of animalswere killed randomly at 1, 3 and 6 months after opera- tion to evaluate the material biological compatibility using anatomic, X-ray examination, histological and ECTmethods.Results: The histological photographs showed that Sr-HA caused little infection around implanted area and, almost was not repulsed by hosts. With the degradation of biomaterial, there was more apparent new bone growth in the area around Sr-HA than that around HA and some ossification can be found in soft tissue nearby. Also a tight osteointegrity was gradually got after the operation, ac- cording to the results of X-ray and, the border between Sr-HA and bone was hardly discovered at the 6th month after the opera- tion. Amore obvious nuclide assembling was observed at the side of Sr-HA by ECTimages. With the biodegradation of Sr-HA, more new bone was intruded into the spare space of the biomaterial.Conclusion:Sr-HA has better biocompatibility and higher biodegradation than thatof pure HA. Itholds an excellentosteoinductivity and fairosteoconductivity to some degree too. So a more satisfying effect of bone defect rehabilitation was gained with the increasing new bone depositing in the free space of the material, when it degraded gradually.

Key words: Sr-HA, biodegradation, osteoinductivity, new bone quantity