光动力疗法对侧支根管内粪肠球菌杀灭作用的实验研究  

Efficacy of Photodynamic Therapy Against Enterococcus Faecalis within Infected Lateral Canals Simulated in vivo

作　　者：孙盼盼[1] 邹朝晖[1] 陶亚东[1] 郭鹏[1] 阴慧娟[2] 

机构地区：[1]天津医科大学口腔医学院,天津市300070 [2]中国医学科学院生物医学工程研究所

出　　处：《中国激光医学杂志》2012年第6期370-374,共5页Chinese Journal of Laser Medicine & Surgery

摘　　要：目的观察光动力疗法(Photodynamic therapy,PDT)对离体牙侧支根管内粪肠球菌的杀灭作用。方法选取人类单根管离体前牙60颗,随机分为3组。常规根管预备后,在牙的近远中面距离根尖孔3 mm处制备15#K锉直径(锉尖直径为150μm)的人工侧支根管,建立粪肠球菌感染模型。实验组为PDT组,以40μg/ml血卟啉单甲醚(Hemato-porphyrin monomethylether,HMME)为光敏剂,避光孵育5 min后用激光功率为80 mW的532 nm半导体激光在根管内上下提拉螺旋照射120 s;阳性对照组为5.25%次氯酸钠冲洗组;阴性对照组为生理盐水冲洗组。各组实验牙标本(每个离体牙近中面侧支根管作为实验前标本,远中面侧支根管作为对应的实验后标本)处理前与处理后即刻用20#K锉取侧支根管内碎屑,然后将碎屑转至含5 ml TPY液体培养基的试管中,10倍递增连续稀释后厌氧培养24 h,菌落计数并推算对应的菌液浓度。结果菌落计数统计结果显示:(1)与阴性对照组(生理盐水冲洗组)比较,HMME-PDT处理组和阳性对照组(5.25%次氯酸钠冲洗组)各侧支根管内细菌量均显著下降(P<0.01);(2)HMME-PDT对侧支根管内粪肠球菌的杀灭效果(92.56%)显著优于阳性对照组(76.93%),差异有显著意义(P<0.01)。结论 HMME-PDT对侧支根管内粪肠球菌有很好的杀灭作用,将为根管消毒提供一种新的有效途径。Objective The purpose of this study is to assess the antibacterial effects of photodynamic therapy on enterococcus faecalis within infected lateral canals simulated in vivo. Methods Extracted teeth（n=60） with single straight canals were prepared chemomechanically,and a standardized lateral canal was simulated at the place 3mm away from the apical foramen（AF） of each tooth with a K-file size of 15.After the preparation,the specimens were divided into three groups（each containing 20 teeth）,namely,the PDT group,negative control group and positive control group.The specimens in the negative control group and the positive group were irrigated with physiological saline and 5.25% NaClO respectively.For the PDT group,the root canal systems were incubated with HMME at a concentration of 40μg/ml for 5min,and then exposed to 532nm light with a power of 80mW for 120s in a spiral pattern.Microbial samples（the dentin chips from simulated lateral canals） were taken respectively before and after the treatment.The survival fractions in each simulated lateral canal were calculated with counting colony-forming units（CFUs）. Results（1） Compared with the negative control group,either the HMME-PDT-treated group or NaClO-treated group had a more remarkable reduction（P〈0.01） in the number of enterococcus faecalis within the simulated lateral canals.（2）The antibacterial effect（92.56%） of the HMME-PDT group was much better than that（76.93%） of the positive control group,and the difference was statistically significant（P〈0.01）. Conclusions HMME-PDT is a highly effective measure against enterococcus faecalis within infected simulated lateral canals.

关 键 词：血卟啉单甲醚 光动力疗法 粪肠球菌 侧支根管 根管治疗 

分 类 号：R781.05[医药卫生—口腔医学]