扫描电镜评价MTAD对根尖区管间峡部感染物的清除效果  

Disinfection effects of MTAD on apical isthmus of the root canal system: a scanning electron microscopic evaluation

作　　者：包旭东[1] 姚娜[2] 郭惠杰[3] 张成飞 岳林[1] 

机构地区：[1]北京大学口腔医学院·口腔医院牙体牙髓科,北京100081 [2]北京大学口腔医学院·口腔医院第二门诊部,北京100081 [3]北京大学人民医院口腔科,北京100044 [4]Endodontics,Comprehensive Dental Care,Faculty of Dentistry,The University of Hong Kong,Hong Kong Special Administrative Region

出　　处：《北京大学学报（医学版）》2012年第1期34-38,共5页Journal of Peking University:Health Sciences

摘　　要：目的:评价MTAD根管冲洗剂清除根尖区峡部感染物的效果。方法:收集有管间峡部结构的上颌第一前磨牙15颗,建立粪肠球菌感染根管模型,分为5组,每组3颗。第1组不做根管预备,作为粪肠球菌感染状态的基线对照,其余4组采用Protaper旋转镍钛锉进行根管机械预备,冲洗分别用生理盐水、MTAD、次氯酸钠和次氯酸钠+EDTA。根管预备后制备扫描电镜标本,观察管间峡部表面细菌群落和玷污层的状态。结果:生理盐水组峡部表面厚层玷污层中嵌有大量细菌,玷污层评分中位数为5;MTAD组峡部表面也铺有玷污层,但玷污层评分较小,中位数为3,嵌入其中的细菌有破壁现象;次氯酸钠组峡部表面铺满牙本质泥,中位数也为5,但不含细菌;次氯酸钠+EDTA组峡部表面干净,牙本质小管和管间结构清晰,玷污层评分的中位数最小为1。结论:MTAD可渗入根尖区管间峡部,部分去除玷污层,但杀菌效果较弱;次氯酸钠配合EDTA冲洗可有效清除管间峡部的感染。Objective： To evaluate the disinfection efficacy of MTAD on Enterococcus faecalis biofilm and smear layer colonization in apical isthums of the root canal system.Methods： Fifteen extracted human maxillary first premolars with isthmus anatomic structure which confirmed by stereo-microscope were contaminated with E.faecalis in vitro and randomly divided into 5 groups： the first group was not treated serving as a baseline control,the second group was treated by normal saline（NS） serving as negative control,the third group was treated by MTAD,the forth group by 5.25% NaOCl,and the fifth group by 5.25% NaOCl ＋ EDTA.All roots in the latter four groups were instrumented by Protaper rotary files and irrigated with respective irrigant,then the roots were split longitudinally and a scanning electron microscope was used to evaluate the antibacterial activity and smear layer cleaning ability of irrigants on isthmus.Results： In the first group,E.faecalis colonized on the isthmus surface and aggregated together to form biofilm-like microorganism community,some bacteria also colonized in the dentinal tubules.When treated with NS,both smear layer and bacteria remained（median of smear layer score was 5）.MTAD can remove partial smear layer,and have limited antibacterial activity,some bacteria embedded in smear layer（the median was 3） and were destroyed;In 5.25% NaOCl treatmentgroup,the smear layer was not removed（median of smear layer score was also 5）,but all bacteria on the surface were extinguished.The combined use of 5.25% NaOCl and EDTA produced a cleaner isthmus surface and had marked antimicrobial effect,with the median of smear layer score being only 1.Conclusion： MTAD may permeate into the isthmus area of apical root canal system,but only performed a partial effect of disinfection and limited antibacterial activity.Sodium hypochlorite cooperated with EDTA can remove infection effectively in the isthmus area.

关 键 词：根尖周炎 根管冲洗剂 肠球菌 粪 次氯酸钠 

分 类 号：R781.341[医药卫生—口腔医学]