氯化镧对根管内粪肠球菌抗菌效果的体外实验

The in vitro antimicrobial effect of lanthanum chloride against Enterococcus faecalis

目的:研究氯化镧、FC、CP、氢氧化钙丙二醇糊剂4种根管消毒剂对离体牙根管内粪肠球菌的抗菌性能。方法:选取72个新鲜拔除的单根管前磨牙,随机分为4个实验组(氯化镧组、FC组、CP组、氢氧化钙丙二醇糊剂组)、1个阴性对照组和1个阳性对照组,每组12个牙。所有牙清理根管后灭菌,除阴性对照组不感染细菌外,其余各组均建立粪肠球菌感染根管模型。建模后,4个实验组分别在根管内放置氯化镧药液、FC、CP、氢氧化钙丙二醇糊剂;阴性和阳性对照组放置生理盐水,37℃、50 mL/L CO2培养箱内培养。分别于培养后3 d和7 d时,取各组根管内壁牙本质粉末用BHI培养基继续培养72 h,比浊仪检测各样本的浊度。结果:①药物处理第3天时,氯化镧组牙本质小管中残留菌量较阳性对照组少,但高于阴性对照组和FC组、氢氧化钙丙二醇糊剂组(P<0.05),与CP组无显著性差异(P>0.05);②药物处理第7天时,FC组、CP组、氢氧化钙丙二醇糊剂组和氯化镧组4种消毒剂牙本质小管内残留细菌量较阳性对照组有明显减少(P<0.05),与阴性对照组相比,差异均无统计学意义(P>0.05)。结论:根管内放置氯化镧药液7 d可有效抑制粪肠球菌生长。

AIM：To evaluate the antibacterial activity of lanthanum chloride,FC,CP,and calcium hydroxide mixed with propylene glycol on Enterococcus faecalis in root canals of extracted teeth.METHODS：Seventy-two freshly extracted single-root premolars were collected and divided randomly into 6 groups,with 12 teeth in each group.After cleaning and sterilization,sixty root canals were infected with Enterococcus faecalis to establish Enterococcus faecalis infected models,the other 12 uninfected root canals served as negative control.The infected root canals were treated with lanthanum chloride,FC,CP,and propylene glycol-calcium hydroxide paste respectively.The root canals of the negative control and positive control groups were treated with 0.9% sodium chloride solution.All roots were incubated at 37 ℃（50 mL/L CO2）.3 and 7 days after incubation,inner dentin powder was taken and further incubated in BHI for 72 h.The turbidity of bacterial suspension was measured by turbidimetry.RESULTS： Three days after root canal treatment,the turbidity of dentin powder suspension was as follows： FC〈propylene glycol-calcium hydroxide〈CP〈lanthanum chloride.No significant difference was found between FC and calcium hydroxide groups（P〉0.05）.Seven days after root canal treatment,the turbidity of all groups further decreased.No significant difference was found among the four treatment groups（P〉0.05）.CONCLUSION：Lanthanum chloride is as effective as FC,CP and calcium hydroxide on inhibiting Enterococcus faecalis growth in root canals ex vivo.