光动力疗法和二极管激光对粪肠球菌生物膜作用的研究

The influence of photodynamic therapy and diode laser on Enterococcus faecalis biofilm

目的:研究光动力疗法(photodynamic therapy,PDT)和二极管激光对体外培养的粪肠球菌生物膜的灭菌作用。方法:建立体外培养24 h的粪肠球菌生物膜模型48个,随机分为4组(n=12),PDT组和975 nm二极管激光(diode laser,DL)作为实验组,2.5%的NaClO(NaClO)和生理盐水(normal saline,NS)分别作为阳性和阴性对照组,标本处理后激光共聚焦显微镜(confocal laser scanning microscope,CLSM)观察各组生物膜中活菌、死菌的变化,平板细菌计数法检测生物膜内粪肠球菌的活力。结果:NaClO组、PDT组和DL组处理后粪肠球菌的菌量显著下降(P<0.05),3组间两两比较差异无统计学意义(P>0.05)。结论:光动力疗法和975 nm二极管激光可以有效地杀灭生物膜内的粪肠球菌,效果与2.5%的NaClO相似。

Objective： To study the influence of photodynamic therapy（PDP） and laser diode （LD） on Enterococcus faecalis biofilm. Methods ：48 Enterococcus faecalis biofilm models were established and divided into 4 groups（ n = 12） ： PDT group, DL group, NaC10 group and normal saline（NS） group. The biofilms were treated by the corresponding methods, Enterococcusfaecalis in biofilms was ob- served by confocal laser scanning microscope （CLSM） and colony forming unit （CFU） assay. Results： PDT, DL and NaC10 reduced the number of Enterococcus faecalis in biofilms significantly more than NS （P 〈 0.05 ）, No difference was observed among PDT, DL and NaC10 groups. Conclusion： PDT and 975 nm diode laser are effective for the sterilization of Enterococcus faecalis in biofilms, the bac- tericidal efficacy is comparable with NaC10.