MTAD对根管内粪肠球菌抗菌效果的体外研究

The inhibitory effects of MTAD irrigation against enterococcus faecalis in vitro

目的评定MTAD对根管内粪肠球菌的抗菌效果。方法在60颗离体牙上建立粪肠球菌根管内感染模型,培养21天。样本被分为3个实验组和2个对照组,实验组分别用MTAD;1.5%Na Cl O/17%EDTA和3%Na Cl O/17%EDTA冲洗。冲洗后,将每个样本放入含有2ml的BHI肉汤中,并离心15秒。然后所有样本放入BHI肉汤中在37°C有氧条件下培养一周。如肉汤有浑浊则认定有粪肠球菌感染。从肉汤无浑浊的样本中提取牙本质碎屑,并置于BHI琼脂板上培养48小时。最后记录有粪肠球菌存在的样本数量。结果培养7天的样本及牙本质碎屑的数据分析显示MTAD较1.5%Na Cl O/17%EDTA和3%Na Cl O/17%EDTA有显著的抗菌活力(P=0.000)。结论 MTAD较Na Cl O和EDTA对粪肠球菌有优越的抗菌性能。

Objective The purpose of this study was to assess the antimicrobial efficacy of MTAD against E. faecalis in contaminated root canals. Methods Sixty single rooted extracted human teeth were inoculated with E. faecalis and incubated for 21 days. The samples were divided into two control and three experimental groups. Three experimental groups irrigated with MTAD; 1.5% NaC10/17% EDTA; or 3% NaC10/17% EDTA. Following irrigation, each tooth was immersed in 2mL of BHI and vortexed for 15s. Teeth were then transferred into tubes containing fresh BHI and incubated for one week at 37℃ under aerobic conditions. We had identified Enterococcus faecalis infection according to muddy broth. Shavings were taken from those samples that exhibited no turbidity, then they were collected on BHI agar lates and incubated for 48h. Finally we recorded number of samples which had existed Enterococcus faecalis. Results Statistical analysis of the data obtained at Day 7 and after dentin shaving analysis showed that MTAD had significantly greater antibacterial activity than 1.5% NaC10/17% EDTA and 3% NaC10/17% EDTA （P=0.000）. Conclusion These findings suggest that MTAD compared with NaC10 and EDTA possesses superior bactericidal activity against Enterococcus faecalis.