Department of Endodontics, Faculty of Dentistry, University of Hacettepe, Ankara, Turkey.
Private Practice, Ankara, Turkey.
Acta Odontol Scand. 2020 Aug;78(6):409-416. doi: 10.1080/00016357.2020.1733076. Epub 2020 Feb 27.
The aim of this study was to evaluate the effect of different irrigation methods on sodium hypochlorite (NaOCl)/debris extrusion and dentinal tubule penetration of 2.5% NaOCl in the presence of an apically separated instrument. Sixty root canals of freshly extracted mandibular single-rooted premolars were chemomechanically prepared up to ProTaper F2. Manual needle irrigation (30-gauge/side-vented) with 2.5% NaOCl was performed between files and a smear layer was removed with 17% ethylenediaminetetraacetic acid. Three mm of notched ProTaper F3 files were separated in the apical third of the roots. Samples were then randomly divided according to the final irrigation systems as follows: EndoActivator, EndoVac, manual needle irrigation, passive ultrasonic activation, and RinsEndo. Samples were mounted to Eppendorf tubes and root canals were irrigated with 3-mL Rhodamine B-labelled 2.5% NaOCl, which was applied using one of the above-mentioned methods. The extruded NaOCl/debris weight was calculated by extracting pre-irrigation weights of tubes from post-irrigation ones. Samples embedded in acrylic resin were sectioned transversely in 1-mm thicknesses at apical 1- and 3-mm levels. NaOCl's penetration depth and percentage into the dentinal tubules were evaluated with the aid of a confocal laser scanning microscope. Data were analysed statistically with Kruskal-Wallis and Siegel-Castellan tests ( < .05). EndoVac significantly decreased the extruded NaOCl/debris compared to RinsEndo, passive ultrasonic activation, and EndoActivator in the presence of a separated instrument ( < .05). The penetrability of NaOCl significantly increased with the use of RinsEndo and EndoVac compared to the remaining groups ( < .05). In the presence of an irretrievable separated instrument, it could be suggested that devices with apical negative pressure such as EndoVac may improve the penetrability of irrigation solutions to the apical part of the root while preserving periapical tissues from NaOCl/debris extrusion.
本研究旨在评估不同冲洗方法对 2.5%次氯酸钠（NaOCl）/根管内玷污层去除和牙本质小管内渗透的影响，同时使用可折断 ProTaper F2 器械。对 60 颗下颌单根前磨牙的新鲜离体牙进行根管机械预备至 ProTaper F2，采用手动侧方冲洗（30 号/侧孔）和 17%乙二胺四乙酸（EDTA）去除玷污层，然后将 3mm 有缺口的 ProTaper F3 锉在根尖 3mm 处折断。然后根据最终冲洗系统将样本随机分为以下几组：EndoActivator 组、EndoVac 组、手动侧方冲洗组、超声冲洗组和 RinsEndo 组。将样本安装在 Eppendorf 管中，用上述方法之一向根管内注入 3ml 罗丹明 B 标记的 2.5%NaOCl。通过从冲洗后的管中提取预冲洗管的重量来计算挤出的 NaOCl/玷污层的重量。将样本嵌入丙烯酸树脂中，在根尖 1mm 和 3mm 处沿根管以 1mm 的厚度横向切片。使用共聚焦激光扫描显微镜评估 NaOCl 的渗透深度和百分比进入牙本质小管。使用 Kruskal-Wallis 和 Siegel-Castellan 检验（ < .05）对数据进行统计学分析。与 RinsEndo、超声冲洗组和 EndoActivator 组相比，在可折断器械存在的情况下，EndoVac 组显著减少了挤出的 NaOCl/玷污层（ < .05）。与其余组相比，使用 RinsEndo 和 EndoVac 显著增加了 NaOCl 的渗透性（ < .05）。在可折断器械无法取出的情况下，使用具有根尖负压的器械（如 EndoVac）可以提高冲洗液渗透到根尖部分的能力，同时防止根尖周组织受到 NaOCl/玷污层的挤出。
