Endodontic Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Department of Periodontology, Dental Faculty - Laser Research Center in Medical Sciences, AJA University of Medical Sciences, Tehran, Iran; International Network for Photo Medicine and Photo Dynamic Therapy (INPMPDT), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
Photodiagnosis Photodyn Ther. 2018 Dec;24:44-51. doi: 10.1016/j.pdpdt.2018.08.010. Epub 2018 Aug 18.
Complete elimination of bacteria and their by-products from the root canal system is very difficult with current techniques. The purpose of this study was to compare the antibacterial efficacy of different disinfection protocols against Enterococcus faecalis (E. faecalis) biofilms.
Seventy-six extracted single-rooted human teeth were selected. Root canal preparation was done by proTaper rotary instruments. The smear layer was removed by 17% EDTA, followed by 5.25% sodium hypochlorite. After sterilization using gamma irradiation, sterilized specimens were inoculated with an E. faecalis suspension, incubated for 4 days and 4 weeks and then randomly divided into two experimental groups (4 days, 4 weeks old biofilms). After the confirmation of biofilm formation with SEM, the specimens in the experimental groups were randomly divided into five experimental subgroups according to the method of disinfection applied, which included: Diode laser irradiation (810 nm, 2 W), Light activated disinfection (LAD) with Indocyanine Green, 0.2% Chlorhexidine gluconate (0.2% CHX), 0.2% CHX + LAD and 0.2% CHX + Diode groups.
Complete biofilm bacterial elimination was not observed in either of the experimental groups. CHX + LAD (0.2%) method exhibited the highest reduction value in biofilm and only Diode alone revealed the lowest in all the root canal portions. Disinfection protocols also showed significantly lower antibacterial efficacy against 4-week old than the 4-day old matured biofilms (P < 0.05).
All the evaluated methods in this study were effective in the relative elimination of the E. faecalis biofilms except diode laser alone. Nevertheless, 0.2% CHX + LAD exhibited significantly higher efficacy in reducing both 4-day and 4-week old biofilms.
目前的技术很难从根管系统中完全清除细菌及其产物。本研究旨在比较不同消毒方案对粪肠球菌（E. faecalis）生物膜的抗菌效果。
选择 76 颗离体单根人牙。采用 proTaper 手用镍钛锉进行根管预备，用 17% EDTA 去除玷污层，再用 5.25%次氯酸钠冲洗。经γ射线消毒后，将消毒标本接种粪肠球菌悬液，孵育 4 天和 4 周，然后随机分为两组实验（4 天和 4 周成熟生物膜）。SEM 确认生物膜形成后，根据应用的消毒方法将实验组标本随机分为五组实验亚组，包括：二极管激光照射（810nm，2W）、吲哚菁绿光动力消毒（LAD）、0.2%葡萄糖酸氯己定（0.2% CHX）、0.2% CHX+LAD 和 0.2% CHX+二极管组。
在任何实验组中均未观察到完全清除生物膜内的细菌。0.2% CHX+LAD 组对生物膜的减少值最高，只有二极管激光单独照射组在所有根管部位的抑菌效果最低。消毒方案对 4 周成熟生物膜的抗菌效果也明显低于 4 天成熟生物膜（P<0.05）。
除单独使用二极管激光外，本研究评估的所有方法对粪肠球菌生物膜的相对消除均有效。然而，0.2% CHX+LAD 组在减少 4 天和 4 周成熟生物膜方面表现出显著更高的效果。
