Department of Endodontics, Bauru Dental School of Bauru, University of São Paulo, Bauru, São Paulo, Brazil.
J Endod. 2011 Aug;37(8):1134-8. doi: 10.1016/j.joen.2011.04.013. Epub 2011 May 28.
The aim of this study was to evaluate the biofilm dissolution and cleaning ability of different irrigant solutions on intraorally infected dentin.
One hundred twenty bovine dentin specimens were infected intraorally by using a removable orthodontic device. Thirty samples were used for each irrigant solution: 2% chlorhexidine and 1%, 2.5%, and 5.25% sodium hypochlorite (NaOCl). The solutions were used for 5, 15, and 30 minutes and at 2 experimental volumes, 500 μL and 1 mL. The samples were stained by using acridine orange dye before and after the experiments and evaluated by using a confocal microscope. The percentage of biofilm, isolated cells, and noncolonized dentin was measured by using a grid system. Differences in the reduction or increase of the studied parameters were assessed by using nonparametric methods (P < .05).
The higher values of biofilm dissolution and noncolonized dentin were found in the 30-minute NaOCl group and in the 5-minute and 15-minute groups of 5.25% NaOCL. The use of 2% chlorhexidine solution did not improve the biofilm dissolution or increase the cleaning of the dentin in comparison with the NaOCl solutions (P < .05).
Two percent chlorhexidine does not dissolve the biofilms. Thirty minutes of NaOCl are necessary to have higher values of biofilm dissolution and to increase the cleaning of the dentin independently of the concentration in comparison with the 5-minute and 15-minute contact times.
本研究旨在评估不同冲洗液对口腔内感染牙本质生物膜溶解和清洁能力。
使用可移动正畸装置将 120 个牛牙本质标本进行口腔内感染。每种冲洗液各有 30 个样本：2%洗必泰（chlorhexidine）和 1%、2.5%、5.25%次氯酸钠（sodium hypochlorite，NaOCl）。使用两种实验体积（500 μL 和 1 mL），冲洗液作用时间分别为 5、15 和 30 分钟。实验前后使用吖啶橙染料对标本进行染色，并使用共聚焦显微镜进行评估。通过网格系统测量生物膜、分离细胞和未定植牙本质的百分比。采用非参数方法（P <.05）评估研究参数减少或增加的差异。
在 30 分钟 NaOCl 组和 5.25% NaOCl 的 5 分钟和 15 分钟组中，生物膜溶解和未定植牙本质的比例最高。与 NaOCl 溶液相比，使用 2%洗必泰溶液并不能改善生物膜溶解或增加牙本质清洁（P <.05）。
2%洗必泰不能溶解生物膜。与 5 分钟和 15 分钟接触时间相比，30 分钟的 NaOCl 可获得更高的生物膜溶解值，并提高牙本质清洁度，而与浓度无关。
