Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilian University of Munich, Munich, Germany.
J Endod. 2012 May;38(5):636-41. doi: 10.1016/j.joen.2011.12.037. Epub 2012 Feb 11.
On extrusion, endodontic sealers might come into close contact with the periapical tissues for long periods. The objective of this study was to test possible mutagenicity of resin-based endodontic sealers by evaluating their potential to induce DNA double-strand breaks (DSBs).
Human gingival fibroblasts were exposed to subtoxic concentrations of eluates from 1 epoxy resin-based endodontic sealer (AH Plus Jet) and 2 methacrylate-based endodontic sealers (EndoRez and Real Seal). As control, Calcicur, a Ca(OH)(2)-based sealer, was used. The γ-H2AX immunofluorescence assay was used to microscopically detect DNA DSBs, and a custom algorithm was developed to quantify them.
The cytotoxicity of the 24-hour eluates could be ranked in the following order: AH Plus Jet > Real Seal > EndoRez >> Calcicur. The γ-H2AX assay revealed that 1.3%-4.3% of the cell nucleus was occupied by foci when the cells were exposed to the eluates of the endodontic sealers. This was not significantly different from the negative control group in which the cells had been exposed to medium (2.1%).
No indications for increased risk of genotoxicity of resin-based root canal sealers caused by the induction of DNA DSBs were found in this study.
在挤出过程中，根管封闭剂可能会长时间与根尖组织密切接触。本研究的目的是通过评估其诱导 DNA 双链断裂（DSB）的能力来测试树脂基根管封闭剂的潜在致突变性。
将人牙龈成纤维细胞暴露于来自 1 种环氧树脂基根管封闭剂（AH Plus Jet）和 2 种甲基丙烯酸酯基根管封闭剂（EndoRez 和 Real Seal）的亚毒性浓度的浸提液中。以 Ca(OH)(2)基封闭剂 Calcicur 作为对照。使用 γ-H2AX 免疫荧光检测法在显微镜下检测 DNA DSB，并开发了一种自定义算法来对其进行定量。
24 小时浸提液的细胞毒性可按以下顺序排列：AH Plus Jet > Real Seal > EndoRez >> Calcicur。γ-H2AX 检测法显示，当细胞暴露于根管封闭剂的浸提液中时，有 1.3%-4.3%的细胞核被焦点占据。这与细胞暴露于培养基（2.1%）的阴性对照组没有显著差异。
在这项研究中，没有发现树脂基根管封闭剂因诱导 DNA DSB 而导致遗传毒性风险增加的迹象。
