de Castro Fábio Pereira Linhares, Pinheiro Sérgio Luiz, Duarte Marco Antônio Húngaro, Duque Jussaro Alves, Fernandes Samuel Lucas, Anchieta Rodolfo Bruniera, da Silveira Bueno Carlos Eduardo
Master's Degree Student in Endodontics, São Leopoldo Mandic Faculty of Dentistry, Campinas, Brazil.
Faculdade de Odontologia-UNIPÓS, Centro Universitário do Norte Paulista-UNORP, São José do Rio Preto, Sao Paulo, Brazil.
Microsc Res Tech. 2016 Nov;79(11):1062-1068. doi: 10.1002/jemt.22746. Epub 2016 Aug 18.
The aim of this study was to assess the effect of time and the ultrasonic activation of ethylenediaminetetraacetic acid (EDTA) in removing the smear layer of at root canal. A total of 60 bovine inferior incisors were transversely sectioned and instrumented; A smear layer was added in the root dentin surface. The specimen were then divided into six groups according to the following final irrigation protocols: Group (G) 1: conventional irrigation with sodium hypochlorite (NaOCl); G2: conventional irrigation with NaOCl + EDTA for 20 s; G3: conventional irrigation with NaOCl + EDTA for 60 s; G4: passive ultrasonic irrigation (PUI) with NaOCl; G5: PUI with NaOCl + PUI with EDTA for 20 s; G6: PUI + NaOCl and PUI with EDTA for 60 s. Samples were analyzed by scanning electron microscope (SEM) at ×500 increase. The images were measured by three blinded evaluators and classified in scores ranging from 1 to 5. The results were analyzed by the Pearson correlation test and the ANOVA nonparametric Kruskal-Wallis and Dunn's tests were used for the comparisons. Irrigated samples only with NaOCl (G1 and G4) had higher scores when compared with other groups. G5 and G6, irrigated with 17% EDTA and ultrasonic irrigation had lower scores. However, there was no statistically significant difference in G2 and G3, where there was no irrigation. It was concluded that irrigation with 17% EDTA for 20 s promoted the effective removal of smear layer, regardless of ultrasonic irrigation.
本研究的目的是评估时间和乙二胺四乙酸（EDTA）的超声激活对去除根管内玷污层的效果。总共60颗牛下颌切牙被横向切割并进行预备；在牙根牙本质表面添加玷污层。然后根据以下最终冲洗方案将标本分为六组：第1组（G1）：用次氯酸钠（NaOCl）进行常规冲洗；G2：用NaOCl + EDTA进行常规冲洗20秒；G3：用NaOCl + EDTA进行常规冲洗60秒；G4：用NaOCl进行被动超声冲洗（PUI）；G5：先用NaOCl进行PUI，再用EDTA进行PUI 20秒；G6：先用NaOCl进行PUI，再用EDTA进行PUI 60秒。通过扫描电子显微镜（SEM）以500倍放大率对样本进行分析。图像由三名不知情的评估人员测量，并分为1至5分。结果通过Pearson相关性检验进行分析，比较采用方差分析的非参数Kruskal-Wallis检验和Dunn检验。与其他组相比，仅用NaOCl冲洗的样本（G1和G4）得分更高。用17% EDTA冲洗并进行超声冲洗的G5和G6得分较低。然而，在未进行冲洗的G2和G3组中没有统计学上的显著差异。得出的结论是，无论是否进行超声冲洗，用17% EDTA冲洗20秒都能有效去除玷污层。
