Study on the development of polycaprolacton silica nanohybrid for bone substitutes / 대한치주과학회지

ABSTRACT

A bioactive and degradable poly(epsilon -caprolactone)/silica nanohybrid(PSH) was synthesized for the application as a bone substitute. PSH was manufactured by using silica and polycaprolacton. PSH was manufactured in some composition after low crystaline apatite had been formed in simulated body fluid and, was used this study. The safety of the PSH was established by test of acute, and subacute toxicity, sensitization cytotoxicity and sterility. In order to assess activity of osteoblast, the test for attaching osteoblast, proliferation test for osteoblast, differentiating gene expression test are performed in vitro. And bone substitutes were grafted in rabbit's calvarium, during 8 weeks for testing efficacy of bone substitutes. Degree of osteogenesis and absorption of substitutes were evaluated in microscopic level. In result, it was not appeared that acute and subacute toxicity, sensitization in intradermal induction phase, topical induction phase and challenge phase. It was shown that the test can not inhibit cell proliferation. adversely, it had some ability to accelerate cell proliferation. The result of sterility test described bacterial growth was not detected in most test tube. The attaching and proliferation test of osteoblast had good results. In the result of differentiating gene expression test for osteoblast, cbfa1 and, alkaline phosphatase, osteocalcin and GAPDH were detected with mRNA analysis. In the PSH bone formation test, ostgeoblastic activity would be different as material constitution but it had good new bone formation ability except group #218. futhermore, some material had been absorbed within 8 weeks. Above studies, PSH had bio-compatibility with human body, new bone formation ability and accelerate osteoblastic activity. So it would be the efficient bone substitute material with bio-active and biodegradable.