DNase Ⅰ与Nd:YAP激光联合应用对根管内粪肠球菌生物膜清除作用的影响

Effects of DNase Ⅰ combined with Nd:YAP laser on the removal of enterococcus faecalis biofilm in root canals

目的 研究脱氧核糖核酸酶Ⅰ(DNase Ⅰ)与Nd:YAP激光联合应用对根管内粪肠球菌(E.f)生物膜的清除效果。方法 建立牙本质片表面E.f感染模型,应用扫描电子显微镜(SEM)观察感染模型建立情况。将25个培养48h的E.f生物膜样本采用随机数字表法分为5组,每组5个。A组:0.5%NaOCl;B组:0.5%NaOCl+Nd:YAP激光;C组:DNase Ⅰ+0.5%NaOCl;D组:DNase Ⅰ+0.5%NaOCl+Nd:YAP激光;E组:生理盐水。激光共聚焦显微镜(CLSM)观察牙本质表面E.f黏附情况,并计数绿色荧光量即为活细菌量。结果 SEM观察可见牙本质表面牙本质小管口开放,E.f黏附聚集在牙本质表面,并见到牙本质小管深层内细菌黏附。CLSM观察可见A、B、C组CLSM图像中绿色荧光的活细菌散在分布于牙本质表面,D组可见较少量的绿色荧光,E组绿色荧光的活细菌覆盖全部样本表面。D组中菌量明显小于A组和E组,C组菌量明显小于E组(P<0.01)。结论 相比于单独使用0.5%NaOCl,DNase Ⅰ联合Nd:YAP激光与0.5%NaOCl冲洗能更有效地处理E.f生物膜。

Objective To study the effect of DNase Ⅰ combined with Nd:YAP laser on the removal of enterococcus faecalis(E.f) biofilm in root canals.Methods The E.f infection model on dentin surface was established and observed by scanning electron microscope(SEM).E.f biofilm samples cultured for 48 h were divided into 5 groups by random number table method,with 5 samples in each group.The group A was treated with 0.5%NaOCl,the group B was treated with0.5%NaOCl+Nd:YAP laser,the group C was treated with DNase I+0.5%NaOCl,the group D was treated with DNase Ⅰ+0.5%NaOCl+Nd:YAP laser and the group E was treated with 0.9% normal saline.The adhesion of E.f on dentin surface was observed by laser confocal microscope(CLSM),and the amount of green fluorescence was counted,which was the amount of viable bacteria.Results SEM observation showed the dentin tubule opening on the dentin surface.E.f adhesion was observed on the dentin surface,and bacterial adhesion was observed in the deep layer of dentin tubule.CLSM observation showed that living bacteria with green fluorescence were scattered on the dentin surface in the group A,the group B and the group C.Less green fluorescence was observed in the group D.Green fluorescent live bacteria covered all the sample surface in the group E.The amount of bacteria in the group D was significantly less than that in the groups A and the groups E,and the amount of bacteria in the group C was significantly less than that in the group E(P<0.01).Conclusion Compared with0.5% NaOCl alone,DNase Ⅰ combined with Nd:YAP laser and 0.5% NaOCl can treat Ef biofilms more effectively.