Effects of Calcium Hypochlorite and Octenidine Hydrochloride on L929 And Human Periodontal Ligament Cells

Abstract The aim of this study was to assess cytotoxicity and cell migration of calcium hypochlorite [Ca(OCl)2] and octenidine hydrochloride - OCT (Octenisept®, Schülke & Mayr, Norderstedt, Germany) in L929 and human periodontal ligament (hPDL) cells. The cells were exposed to different doses of different solutions: 2.5% and 5% Ca(OCl)2, 0.1% OCT, 2.5% NaOCl and 2% CHX for 10 min. Cell viability was assessed by methyl-thiazol-tetrazolium (MTT) and neutral red (NR) assays, and cell migration was determined by wound-healing assay. Statistical analysis was performed by two-way ANOVA and Bonferroni tests (α=0.05). The MTT and NR assays revealed that 0.1% OCT was less cytotoxic in hPDL cells (p<0.05), followed by 2% CHX and 2.5% Ca(OCl)2 (p<0.05). There was no significant difference between 2.5% NaOCl and 5% Ca(OCl)2 (p>0.05), but these solutions showed greater cytotoxicity than the others. The result was the same for L929 cells, except that there was no significant difference between 2% CHX and 2.5% Ca(OCl)2 (p>0.05). Wound-healing assay in L929 and hPDL cells showed that cell migration of 0.1% OCT, 2% CHX and 2.5% Ca(OCl)2 groups was higher than 5% Ca(OCl)2 and 2.5% NaOCl groups at 24 h (p<0.05). In conclusion, 0.1% OCT had lower cytotoxicity in tested cell lines than CHX, Ca(OCl)2 and NaOCl. Cell migration was higher for 0.1% OCT, 2% CHX and 2.5% Ca(OCl)2. Therefore, in terms of cytotoxicity, OCT and Ca(OCl)2 have the potential to be used as root canal irrigants.

摘要 本研究旨在评估次氯酸钙[Ca(OCl)₂]与盐酸奥替尼啶（OCT，商品名Octenisept®，Schülke & Mayr公司，德国诺德施泰特）对L929细胞及人牙周膜（human periodontal ligament, hPDL）细胞的细胞毒性与细胞迁移能力的影响。将细胞暴露于不同浓度的多种溶液中10 min，包括2.5%与5%次氯酸钙、0.1% OCT、2.5%次氯酸钠（NaOCl）以及2%氯己定（CHX）。采用甲基噻唑基四唑（methyl-thiazol-tetrazolium, MTT）法与中性红（neutral red, NR）法检测细胞存活率，通过伤口愈合实验测定细胞迁移能力。统计分析采用双向方差分析（two-way ANOVA）与Bonferroni检验（检验水准α=0.05）。
MTT与NR实验结果显示，0.1% OCT在hPDL细胞中的细胞毒性最低（p<0.05），其次为2% CHX与2.5%次氯酸钙（p<0.05）；2.5% NaOCl与5%次氯酸钙的细胞毒性无显著差异（p>0.05），但二者的细胞毒性均高于其余受试溶液。对于L929细胞，结果趋势一致，仅2% CHX与2.5%次氯酸钙的细胞毒性无显著差异（p>0.05）。L929与hPDL细胞的伤口愈合实验结果表明，培养24 h时，0.1% OCT、2% CHX及2.5%次氯酸钙组的细胞迁移能力显著高于5%次氯酸钙与2.5% NaOCl组（p<0.05）。
综上，在受试细胞系中，0.1% OCT的细胞毒性低于CHX、次氯酸钙与NaOCl；0.1% OCT、2% CHX及2.5%次氯酸钙组的细胞迁移能力更高。因此从细胞毒性角度而言，OCT与次氯酸钙有望作为根管冲洗剂使用。