Provoost Charley, Rocca Giovanni Tommaso, Thibault Anna, Machtou Pierre, Bouilllaguet Serge
University Clinics of Dental Medicine, University of Geneva, 1207 Geneva, Switzerland.
Dent J (Basel). 2022 Apr 2;10(4):59. doi: 10.3390/dj10040059.
This study aimed to evaluate the influence of needle design and irrigant flow rate on the removal of Enterococcus faecalis mature biofilms during sodium hypochlorite irrigation. Forty-eight single-rooted human teeth were instrumented (ProTaper F3), autoclaved and inoculated with Enterococcus faecalis to establish a two-week-old biofilm. E. faecalis biofilms were treated with Sodium hypochlorite that was injected in the root canals using three types of needles (NaviTip, ProRinse, IrriFlex). For the IrriFlex needle, one, two, or four bars of pressure was applied to the irrigating solution to increase flow rates. Bacteria were labeled with the LIVE/DEAD BacLight Bacterial Viability kit, and viability was assessed by flow cytometry (FCM). Results were statistically analyzed using one-way ANOVA and Tukey multiple comparison intervals (α = 0.05). Bacterial viability was significantly reduced after sodium hypochlorite passive irrigation but the number of viable bacteria retrieved from root canal specimens irrigated with the Pro-Rinse needle was significantly higher compared to NaviTip and IrriFlex needles (p < 0.05). When the irrigant flow rate was increased, the viability of bacterial biofilms was significantly reduced compared to passive irrigation using the IrriFlex needle (p < 0.05). Applying higher flow rates during irrigation using the IrriFlex needle did not further reduce bacterial viability.
本研究旨在评估在次氯酸钠冲洗过程中，针具设计和冲洗液流速对粪肠球菌成熟生物膜清除的影响。选取48颗单根人牙进行预备（使用ProTaper F3器械），高压灭菌后接种粪肠球菌以形成两周龄的生物膜。使用三种类型的针具（NaviTip、ProRinse、IrriFlex）将次氯酸钠注入根管，对粪肠球菌生物膜进行处理。对于IrriFlex针具，对冲洗液施加一、二或四个压力档以提高流速。使用LIVE/DEAD BacLight细菌活力试剂盒对细菌进行标记，并通过流式细胞术（FCM）评估活力。结果采用单因素方差分析和Tukey多重比较区间进行统计学分析（α = 0.05）。次氯酸钠被动冲洗后细菌活力显著降低，但与NaviTip和IrriFlex针具相比，用Pro-Rinse针具冲洗的根管标本中回收的活菌数量显著更高（p < 0.05）。当冲洗液流速增加时，与使用IrriFlex针具进行被动冲洗相比，细菌生物膜的活力显著降低（p < 0.05）。使用IrriFlex针具冲洗时施加更高的流速并未进一步降低细菌活力。
