不同根管冲洗方式对粪肠球菌生物膜清除效果评价

目的:比较不同根管冲洗方式对粪肠球菌感染根管预备、冲洗的清除效果,评价不同根管冲洗液残余药量的抗菌效果,为临床上选择根管冲洗方法提供参考。方法:将32颗离体牙(前磨牙、单根管)消毒,接种粪肠球菌60 d,随机分为4组(第1组:生理盐水;第2组:生理盐水+超声1 min;第3组:1%NaOCl;第4组:1%NaOCl+超声1 min),使用ProTaper器械按照冠向下法进行根管预备,并在预备冲洗前及预备至F2进行冲洗后分别取样、计数,进行统计学分析。将预备好的离体牙再次消毒,随机分为2组,分别浸泡生理盐水和1%NaOCl;浸泡30 min后取出,置于接种粪肠球菌标准菌株(ATCC33186)的培养液内,分别在培养2、6、24、48 h时取样、计数。采用SPSS19.0软件包对数据进行统计学分析。结果:4组在预备至F2冲洗结束后,根管中的细菌数量均不同程度降低,其中,使用1%NaOCl结合超声冲洗1 min,几乎可完全去除根管内的细菌。经1%NaOCl浸泡的牙根样本内的细菌,在培养48 h时后总量少于生理盐水。结论:1%NaOCl是有效的根管冲洗液,用于根管化学预备后的残余液体,也可发挥有效的抗菌效果。联合使用超声器械,可以使其抗菌效果最大化。

In vitro study of antimicrobial efficacy of different irrigations on Enterococcus faecalis biofilm formation in root canal

PURPOSE: To compare the antimicrobial effect of different irrigations on Enterococcus faecalis biofilms in extracted teeth and evaluate the antimicrobial activity of irrigating solutions residual against E. faecalis biofilms formation, in order to provide a better strategy for clinician. Methods: Extracted human premolar teeth with single root canal were clearly autoclaved. These teeth were contaminated with E. faecalis（ATCC33186） and incubated for 60 days. The samples were randomly assigned to 4 experimental groups. During biomechanical instrumentation, the root canal was irrigated with different irrigating agents. The bacteria samples were collected with sterile paper points before and after instrumentation to F2. Then, samples that had been instrumented and autoclaved again were randomly divided into 2 groups treated with normal saline and 1%NaOCl for 30 min. E. faecalis was used to contaminate these root canals. The bacteria samples were collected with sterile paper points after 2, 6, 24, 48 h. SPSS19.0 software package was used for statistical analysis. Results: Group using 1% NaOCI with ultrasound devices was significantly more effective than NS alone groups. 1% NaOCI groups showed a better residual activity than NS group. Conclusions: NaOCl is still the most important irrigating solutions, and it could be a better choice after biomechanical instrumentation, because of its long time substantivity achieves residual antimicrobial activity. Ultrasound devices is recommended to coordinate with irrigation.