Er:YAG激光联合不同根管冲洗剂对根管内粪肠球菌杀灭效果的研究

Antimicrobial effect of Er: YAG laser combined with different root canal irrigants on Enterococcus faecalis

目的:比较观察Er:YAG激光联合不同根管冲洗剂对根管内粪肠球菌的杀灭效果。方法:建立粪肠球菌感染根管模型的120个样本,随机分成6组,每组20个,从每组中各随机抽取10个样本,检测不同深度根管壁中的细菌数作为基线;各组所余的另10个样本按相应分组分别进行如下处理:A组用Er:YAG激光+52.5 g/L次氯酸钠+生理盐水+蒸馏水处理,B组用Er:YAG激光+强酸性电解质水+生理盐水+蒸馏水处理,C组用Er:YAG激光+30 mL/L过氧化氢液+生理盐水+蒸馏水处理;D组用Er:YAG激光+生理盐水+蒸馏水处理,E组用52.5 g/L次氯酸钠溶液处理(阳性对照);F组用生理盐水处理(阴性对照)。最后采集各组处理前后样本的根管壁表面和不同深度(0~100、100~200、200~300μm)的牙本质进行细菌培养计数。结果:A^E各组对根管壁表面以及不同牙本质深度中的细菌清除率均显著高于F组(P<0.05);A^E各组对根管壁表面和0~100μm深度的细菌清除率基本相似(P>0.05);当深度为100~200μm和200~300μm时,A、B、E 3组仍保持较高的细菌清除率,3组间比较P>0.05,而C、D 2组的细菌清除率则低于A、B、E各组(P<0.05),D组明显低于C组(P<0.05)。结论:Er∶YAG激光分别与次氯酸钠、强酸性电解质水联合,能有效清除不同深度牙本质中粪肠球菌。

AIM： To compare the antimicrobial effect of Er：YAG laser combined with different root canal irrigants on Enterococcus faecalis in root canal. METHODS ： 120 single-rooted human teeth infected with Enterococcus faecalis for 4 weeks were randomly divided into 6 groups （n = 20）. From each group, 10 teeth were randomly selected and the dentin bacterial counts at different depths were measured and served as baseline data. The rest teeth of each group were treated with Er ： YAG laser ＋ 52.5 g/L NaClO ＋ normal saline （ NS ） ＋ distilled water （ DW ） （ group A ） , Er ： YAG laser ＋ strong acid electrolytic water （SAWE） ＋ NS ＋ DW （ group B ）, Er ： YAG laser ＋ 30 mL/L H2O2 ＋ NS ＋ DW（ group C） ; Er： YAG laser ＋ NS ＋ DW （ group D）, 52.5 g/L NaClO （ group E） and NS （ group. F） respectively. The numbers of bacteria on the surface of root canal wall at different depths （0 - 100, 100 - 200,200 -300μm） inside dentinal tubules before and after treatments were counted and the bacterial reduction were analyzed by means of one-way ANOVA. RESULTS： On the surface and at different depths of dentine, the bactericidal efficiency of group A, B, C, D and E were significantly greater than that of group F （P 〈0.05）. And on the surface and at 0 - 100 μm depth, the bacterial reduction of A, B, C, D and E groups were similar （P 〉 0.05）. At depths of 100 -200 μm and 200 - 300 μm, the groups A, B and E still possessed similarly high bactericidal efficiency （ P 〉 0.05 ）. But the bacte- ricidal efficiency of groups C and D were significantly lower than group A, B and E （ P 〈 0.05 ）. The bacterial reduction in group D and was the least and lower than that in group C （ P 〈 0.05 ）. CONCLUSION ： Er ： YAG laser combined with NaClO or SAEW has strong effects for disinfection of Enterococcus faecalis in root canal at different depths.