Kayaoglu G, Erten H, Alaçam T, Ørstavik D
Department of Endodontics and Conservative Treatment, Faculty of Dentistry, Gazi University, Ankara, Turkey.
Int Endod J. 2005 Jul;38(7):483-8. doi: 10.1111/j.1365-2591.2005.00981.x.
To investigate the antimicrobial activity of root canal sealers on Enterococcus faecalis, either allowing or avoiding direct contact between sealers and bacteria.
Filter paper discs were immersed in standardized E. faecalis suspensions and exposed to freshly mixed sealers (MCS, AH Plus, Grossman's sealer, Sealapex, Apexit) in teflon wells for 30 min, with or without a filter membrane placed between filter paper discs and sealers (membrane-restricted contact test and direct contact test, respectively). After exposure, the filter paper discs were transferred to vials containing phosphate-buffered saline (PBS) and glass beads, and vigorously vortexed. PBS with resuspended bacterial cells was serially diluted and 25 microL droplets were seeded on TSA plates. The plates were incubated in air at 37 degrees C for 24 h and colony-forming units were counted. Using alpha = 0.05 as level for statistical significance, the data obtained were analysed using Student's t-test.
In the direct contact test, MCS and AH Plus killed the bacteria to a level below the detection limit. They were followed in decreasing order of efficacy by Grossman's sealer, Sealapex and Apexit. In the membrane-restricted contact test, the sealers ranked: MCS, AH Plus, Grossman's sealer, Apexit and Sealapex, in descending order of antibacterial potency. MCS, AH Plus and Grossman's sealer significantly reduced the number of viable bacteria in both tests. Sealapex and Apexit were not statistically different from control.
MCS, AH Plus and Grossman's sealer were effective in reducing the number of cultivable cells of E. faecalis. Calcium hydroxide-based sealers, Sealapex and Apexit were ineffective in this short-term experiment.
研究根管封闭剂对粪肠球菌的抗菌活性，包括允许或避免封闭剂与细菌直接接触的情况。
将滤纸圆盘浸入标准化的粪肠球菌悬液中，然后在聚四氟乙烯孔中与新鲜混合的封闭剂（MCS、AH Plus、格罗斯曼封闭剂、Sealapex、Apexit）接触30分钟，分别进行有或没有在滤纸圆盘和封闭剂之间放置滤膜的操作（分别为膜限制接触试验和直接接触试验）。接触后，将滤纸圆盘转移到含有磷酸盐缓冲盐水（PBS）和玻璃珠的小瓶中，并剧烈涡旋。将含有重悬细菌细胞的PBS进行系列稀释，取25微升液滴接种于TSA平板上。平板在37℃空气中孵育24小时，然后计数菌落形成单位。以α = 0.05作为统计学显著性水平，使用学生t检验分析所得数据。
在直接接触试验中，MCS和AH Plus将细菌杀灭至检测限以下水平。其次是格罗斯曼封闭剂、Sealapex和Apexit，按疗效递减顺序排列。在膜限制接触试验中，封闭剂的抗菌效力排序为：MCS、AH Plus、格罗斯曼封闭剂、Apexit和Sealapex，从高到低。在两种试验中，MCS、AH Plus和格罗斯曼封闭剂均显著减少了活菌数量。Sealapex和Apexit与对照组无统计学差异。
MCS、AH Plus和格罗斯曼封闭剂在减少粪肠球菌可培养细胞数量方面有效。基于氢氧化钙的封闭剂Sealapex和Apexit在该短期实验中无效。
