根管封闭剂细胞毒性的比较研究

A comparative study on the cytotoxicity of root canal sealers

目的:比较5种根管封闭剂根管充填后不同时期对L929小鼠成纤维细胞的细胞毒性。方法:选取18个单根前磨牙,截冠,拔髓,定长,根管预备,冲洗后,随机分组,分别用5种不同根管封闭剂(Roeko-seal,AH-plus,CRCS,Vitapex,Apexit)结合1根牙胶尖进行根管充填,冠方用玻璃离子封闭。设只用1根牙胶尖组作为对照。采用MTT比色试验,分别检测各组根管封闭剂根管充填24h、1周和5周后洗脱液的细胞毒性。结果:充填后24h,Roeko seal组无细胞毒性,其余4组都有一定的细胞毒性,其中CRCS组细胞毒性最大,与剩余4组封闭剂有显著的统计学差异(P<0.01);充填后1周,Roeko seal组无细胞毒性,其余4组都有一定的细胞毒性,其中Vitapex组毒性最大,Apexit组次之,两组均与剩余两组有显著的差异(P<0.01);充填后5周,Roeko seal组无细胞毒性,Vitapex组也基本无细胞毒性,其余3组都有一定的细胞毒性,与前两组相比有显著的差异(P<0.01)。结论:①Roeko seal无细胞毒性,是一种生物相容性良好的根管封闭剂。②AH-plus、CRCS、Apexit有一定的细胞毒性,随着时间的推移,其细胞毒性呈现递减的趋势。③Vitapex在初始阶段具有一定的细胞毒性,其大小随时间而递减,在充填后5周时已基本无细胞毒性。

AIM： To compare the cytotoxiclty on L929 mouse fibroblast between five types of root canal sealers at different time after obturation in a root canal model in vitro. METHODS： 18 extracted single -roote premolars were divided into six groups. Each group were instrumented and filled with Roeko - seal, AH - plus, CRCS, Vitapex, or Apexit and one gutta - percha point at random. All root canals were coronally sealed with glass - ionomer cement. Teeth were filled with one gutta - percha point only as controls. All specimens were consecutively extracted with distilled water. The extract of 24 hours, 1 week and 5 weeks of each specimen were investigated for cytotoxicity in L929 fibroblast culture by the MTT assay. RESULTS： In 24 hour groups, Roeko seal showed no cytotoxicity;the rest four kinds of sealer showed cytotoxicity. CRCS displayed the highest degree of cytotoxicity among them and significant difference was found between CRCS and the others（P 〈0.01 ）. In 1 week groups, Roeko seal showed no cytotoxicity; others showed cytotoxicity. Vitapex showed the highest cytotoxicity and followed by Apexit. Significant difference was found between them and other two groups（ P 〈0.01 ）. In 5 week groups, Roeko seal and Vitapex showed no cytotoxicity and had significant difference from the others; the rest three kinds of sealer showed cytotoxicity （P 〈0.01 ）. CONCLUSION： ①）Roeko seal is noncytotoxic. ②AH -plus, CRCS, and Apexit all show cytotoxicity at initial stage and the cytotoxicity show a decreasing trend. ③Vitapex shows cytotoxicity at initial stage, but the cytotoxicity decreases over time, and shows no cytotoxicity in 5 week - extract.