TBO-PDT对根管内粪肠球菌抑制作用的实验研究

发布时间：2019-05-11 02:46

【摘要】：目的:体外观察不同光敏剂浓度和不同激光能量密度的TBO-PDT抑制离体牙根管内粪肠球菌的效果,确定最佳光敏剂参数和激光参数,并在此基础上探讨TBO-PDT在抑制离体牙根管内粪肠球菌上的作用优势,为PDT应用于根管消毒的临床实践提供理论与实验依据。方法:对离体牙进行根管预备,接种粪肠球菌,厌氧培养21d后建立粪肠球菌感染根管模型。将其随机分组:A组为阴性对照组,以生理盐水冲洗根管;B组为阳性对照组,以5.25%NaClO冲洗根管;其余组别根据光敏剂浓度的不同,分为C1组80μg/mL、D1组90μg/mL、E1组100μg/mL、F1组110μg/mL、G1组120μg/mL,避光孵育5min后用波长为630nm功率密度为90mW/cm2半导体激光在根管内上下提拉螺旋照射90s;根据光照时间的不同,分为C2组30s、D2组60s、E2组90s、F2组120s、G2组150s,光敏剂浓度为100μg/mL避光孵育5min后,用波长为630nm功率密度为90mW半导体激光在根管内上下提拉螺旋照射各实验组牙标本,实验处理前后即刻取样,厌氧培养24h,计数平板菌落,明确实验处理前后根管内粪肠球菌的数量变化。结果:(1)不同光敏剂浓度下TBO-PDT对根管内粪肠球菌抑菌效果的影响。平板菌落计数结果显示:不同光敏剂浓度的各组抑菌率随光敏剂浓度的增加而增高。与阴性对照组相比,C1组、D1组、E1组、F1组和G1组的抑菌率显著提高,而F1组和G1组两组间抑菌率没有明显差异。(2)不同光照时间对TBO-PDT抑制实验根管内以生物膜形式存在的粪肠球菌的抑菌效果。平板菌落计数结果显示:不同光照时间的各组抑菌率随光照时间延长而增高。与阴性对照组相比,其中C2组、D2组、E2组、F2组和G2组的抑菌率明显升高,而F2组和G2组两组间抑菌率没有明显差异。结论:TBO-PDT对以生物膜形式存在的粪肠球菌有明显的抑制作用,实验证实TBO-PDT最佳光敏剂浓度为110μg/mL,最佳光照时间为120s。
[Abstract]:Objective: to observe the inhibitory effect of TBO-PDT with different photosensitizer concentration and different laser energy density on Enterococcus faecalis in vitro, and to determine the best photosensitizer parameters and laser parameters. On this basis, the advantages of TBO-PDT in inhibiting Enterococcus faecalis in isolated root canal were discussed, which provided theoretical and experimental basis for the clinical practice of PDT in root canal disinfection. Methods: the root canal model of Enterococcus faecalis infection was established after root canal preparation of isolated teeth and inoculated with Enterococcus faecalis for 21 days. The root canals were randomly divided into two groups: group A as negative control group, group B as positive control group, group A as negative control group, group B as positive control group, and group B as positive control group. The other groups were divided into C1 group 80 渭 g / mL,D1 group 90 渭 g / mL,E1 group 100 渭 g / mL,F1 group 110 渭 g / mL,G1 group 120 渭 g / mL, according to the concentration of photosensitizer. After 5min was incubated with light, 630nm power density was 90mW/cm2 semiconductor laser to irradiate 90 s in root canal with upper and lower Czochralski helix. According to the different light time, they were divided into C2 group (30s), D2 group (60s), E2 group (90s), F2 group (120s) and G2 group (150s). The concentration of photosensitizer was 100 渭 g / mL to avoid light to incubate 5min. The dental specimens of each experimental group were irradiated with 90mW semiconductor laser at the power density of 90mW in the root canal. The samples were sampled immediately before and after the experimental treatment and cultured for 24 hours, and the plate colonies were counted. The quantitative changes of Enterococcus faecalis in root canal before and after experimental treatment were determined. Results: (1) the effect of TBO-PDT on the bacteriostatic effect of Enterococcus faecalis in root canal under different photosensitizer concentrations. The results of plate colony count showed that the bacteriostatic rate of each group with different photosensitizer concentration increased with the increase of photosensitizer concentration. Compared with the negative control group, the bacteriostatic rate of C1 group, D1 group, E1 group, F1 group and G1 group was significantly increased. However, there was no significant difference in bacteriostatic rate between F1 group and G _ 1 group. (2) the bacteriostatic effect of different light time on Enterococcus faecalis in the form of biofilm in root canal of TBO-PDT inhibition test. The results of plate colony count showed that the bacteriostatic rate of each group increased with the prolongation of light time. Compared with the negative control group, the bacteriostatic rate of C2 group, D2 group, E2 group, F2 group and G2 group was significantly higher than that of negative control group, but there was no significant difference between F2 group and G2 group. Conclusion: TBO-PDT has obvious inhibitory effect on Enterococcus faecalis in the form of biofilm. The results show that the optimum photosensitizer concentration of TBO-PDT is 110 渭 g / mL, and the optimum light time is 120 s.
【作者单位】：承德医学院附属医院口腔科;
【分类号】：R781.05

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