Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Department of Endodontics, Centro Universitario Franciscano, Santa Maria, RS, Brazil.
Photodiagnosis Photodyn Ther. 2017 Dec;20:169-174. doi: 10.1016/j.pdpdt.2017.10.003. Epub 2017 Oct 13.
This study aimed to evaluate the antibacterial effect and the biofilm disruption promoted by antimicrobial photodynamic therapy (aPDT) associated with sodium hypochlorite (NaOCl) and chlorexidine (CHX) over monospecies and multispecies biofilms.
In monospecies model, forty-six premolars were inoculated with Enterococcus faecalis for 21days and divided into three groups: saline, CHX and NaOCl. After irrigation, aPDT was performed. Samples were collected at baseline (S1) and after irrigation (S2) and aPDT (S3). Colony-forming unit (CFU) counts were performed. In multispecies model, sixty bovine dentin blocks were infected intraorally for 72h and divided into six groups: saline, saline/aPDT, CHX, CHX/aPDT, NaOCl and NaOCl/aPDT. The percentage and the biovolume of live cells and the total biovolume were assessed using confocal laser scanning microscopy.
CHX and NaOCl showed the lowest CFU counts (P<0.05). aPDT reduced the bacterial counts in saline (S2-S3; P<0.05). The lowest amount of live cells was observed in CHX, CHX/aPDT, NaOCl and NaOCl/aPDT. aPDT did not reduce the total biovolume (P>0.05).
aPDT associated with saline reduced the bacterial load in root canals infected with E. faecalis. aPDT did not reduce the total biovolume in situ; however, the irrigant was decisive to disrupt multispecies biofilms.
本研究旨在评估抗菌光动力疗法（aPDT）联合次氯酸钠（NaOCl）和洗必泰（CHX）对单物种和多物种生物膜的抗菌效果和生物膜破坏作用。
在单物种模型中，将 46 颗前磨牙接种粪肠球菌 21 天，分为生理盐水组、CHX 组和 NaOCl 组。冲洗后，进行 aPDT。分别在基线（S1）、冲洗后（S2）和 aPDT 后（S3）采集样本。进行菌落形成单位（CFU）计数。在多物种模型中，将 60 个牛牙本质块经口内感染 72 小时，分为生理盐水组、生理盐水/aPDT 组、CHX 组、CHX/aPDT 组、NaOCl 组和 NaOCl/aPDT 组。使用共聚焦激光扫描显微镜评估活细胞的百分比和生物体积以及总生物体积。
CHX 和 NaOCl 显示出最低的 CFU 计数（P<0.05）。aPDT 降低了生理盐水组的细菌计数（S2-S3；P<0.05）。CHX、CHX/aPDT、NaOCl 和 NaOCl/aPDT 组观察到的活细胞数量最少。aPDT 未降低总生物体积（P>0.05）。
联合生理盐水的 aPDT 可降低粪肠球菌感染根管内的细菌负荷。原位 aPDT 未降低总生物体积；然而，冲洗液对破坏多物种生物膜具有决定性作用。
