Co-Investigator(Kenkyū-buntansha) |
MATSUO Masatoshi Sumitomo Chemicals, Research Director, 研究主幹
IMAZATO Satoshi Osaka University, Graduate School of Dentistry, Associate Professor., 大学院・歯学研究科, 助教授 (80243244)
EBISU Shigeyuki Osaka University, Graduate School of Dentistry, Professor., 大学院・歯学研究科, 教授 (50116000)
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Budget Amount *help |
¥13,300,000 (Direct Cost: ¥13,300,000)
Fiscal Year 2002: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2001: ¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 2000: ¥7,500,000 (Direct Cost: ¥7,500,000)
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Research Abstract |
Estrogenicity of commercial composites, which contain various monomers and additives, has not yet been fully elucidated. In this study, the estrogenic activities of eluates obtained from 24 composites were examined in vitro (reporter gene assay). The estrogenicity of 18 chemicals identified from the composites was also assessed by a reporter gene assay. Furthermore, the estrogenic activity of the chemicals, which were confirmed to have estrogenic activity in vitro, was examined in vivo (uterotrophic assay). Among 24 composites, six products were estrogenic in vitro, although none of the specimens contained bisphenol-A. Moreover, one photostabilizer (2-hydroxy-4-methoxy-benzophenone, HMBP), one photoinitiator (2,2-dimethoxy-2-phenyl-acetophenone, DMPA), and one inhibitor (2,6-di-tert-butyl-ρ-cresol, BHT) showed significant estrogenic activities among 18 chemicals in vitro. The concentrations of HMBP in 4 estrogenic eluates were greater than the minimum concentration to show estrogenicity. For other 2 estrogenic concentration. In addition, BHT was not identified in any of the eluates. Therefore, the estrogenic activites of composites observed in vitro were associated with the elution of HMBP or DMPA. On the contrary, neither HMBP nor DMPA showed estrogenicity in vivo. These results suggest that the possibilities of the chemicals eluted from resin composites mimicking natural steroid hormones are negligible.
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