Araki K, Suda H, Spångberg L S
Department of Endodontics, Faculty of Dentistry, Tokyo Medical and Dental University, Japan.
J Endod. 1994 Feb;20(2):67-70. doi: 10.1016/S0099-2399(06)81183-0.
The cytotoxicity of two root canal sealers was evaluated in vitro. The powder components of both sealers, mainly zinc, were the same. The liquid for one sealer, Canals, was clove oil (included eugenol in more than 80%) and other materials. For the other, Canals-N, the liquid was composed of higher fatty acids and glycol. The experiments included two cell lines, heteroploid L929 mouse fibroblasts and diploid human periodontal ligament fibroblasts. Cytotoxicity was assessed using the radiochromium release method with 4-h exposure time. The assay involved using insert chambers in multiwell arrays to produce indirect contact of materials with the cell monolayer at a controlled distance of approximately 1 mm. This model also allowed for the longitudinal study of the same material sample to assess time-dependent changes in toxicity. Freshly mixed Canals was highly toxic (p < 0.01) to both cell lines. On and after 24 h of setting no toxicity was detected. At no time could cytotoxicity be observed when experimenting with Canals-N. These results indicate that both materials have a low content of water diffusible toxic components. Substituting eugenol can further decrease the toxicity of the sealer.
在体外评估了两种根管封闭剂的细胞毒性。两种封闭剂的粉末成分主要都是锌，是相同的。一种封闭剂Canals的液体是丁香油（丁香酚含量超过80%）和其他物质。另一种封闭剂Canals-N的液体由高级脂肪酸和二醇组成。实验包括两种细胞系，异倍体L929小鼠成纤维细胞和二倍体人牙周膜成纤维细胞。使用放射性铬释放法在4小时暴露时间下评估细胞毒性。该测定涉及在多孔阵列中使用插入室，以使材料与细胞单层在约1毫米的受控距离处间接接触。该模型还允许对同一材料样品进行纵向研究，以评估毒性随时间的变化。新鲜混合的Canals对两种细胞系都具有高毒性（p < 0.01）。凝固24小时及之后未检测到毒性。在用Canals-N进行实验时，任何时候都未观察到细胞毒性。这些结果表明两种材料中可水溶扩散的有毒成分含量都很低。用丁香酚替代可进一步降低封闭剂的毒性。
