Development of a risk assessment method for dental materials using a bone metabolic system

人们认为，释放到环境中的许多化学物质会破坏人类和动物的正常内分泌功能。这些干扰内分泌的化学物质（EDCs）影响生殖健康和发育。目前，关注的重点是发展体内和体外筛选策略，以识别和分类EDCs，以确定这些化学品是否对人类健康构成危害。在之前的研究中，我们报道了化合物的雌激素活性，受体结合试验，受体基因表达试验，使用培养细胞和酵母细胞，以及酵母双杂交试验。这些筛选试验应用于牙科材料的风险评估。尽管这些方法在检测雌激素性方面很有用，但它们也有局限性。特别是，我们对EDCs是否影响骨形成知之甚少。本研究探讨了口腔材料的遗传毒性和雌激素性的影响。希望能够利用成骨细胞建立体内EDCs和遗传毒性化学物质的生物测定方法，并应用于口腔内牙材料中渗出的化学物质的安全性判断。总结这些研究中进行的各种分析的结果，得出以下结论：1)树脂聚合后，树脂单体和增塑剂等化学物质浸出。2)牙科材料的某些成分具有遗传毒性或雌激素活性。3)暴露于化学物质的成骨细胞中RANKL、OPG、ERα和ERβ mRNA的测定有助于评估骨代谢系统的风险评估。

Many chemicals released into the environment are believed to disrupt normal endocrine functions in humans and anima1s. These endocrine-disrupting chemicals (EDCs) affect reproductive health and development. Currently, attention is focused on the development of in vivo and in vitro screening strategies to identify and classify EDCs, in order to determine whether such chemicals pose a hazard to human health. In previous studies, we reported on the estrogenic activity of compounds, receptor-binding assays, and receptor gene expression assays using cultured cells and yeast cells, and a yeast two-hybrid assay. These screening tests were applied to the risk evaluation of dental materials. Despite the usefulness of these methods for detecting estrogenicity, they have their limitations. In particular, very little is known about whether EDCs affect bone formation. This study investigated the effects of the genotoxicity and estrogenicity of dental materials. It is hoped that a bioassay of EDCs and genotoxic chemicals in vivo can be established, using osteoblasts, and then applied, to judge the safety of the chemicals that leach from dental materials in the mouth. Summarizing the results of the various analyses carried out in these studies, the following conclusions were drawn:1) Chemicals such as resin monomers and plasticizers leach out of dental resins after polymerization.2) Some components of dental materials have genotoxic or estrogenic activity.3) Measurements of RANKL, OPG, ERα, and ERβ mRNA in osteoblasts exposed to chemicals were useful for evaluating risk assessment in a bone metabolic system.