Barreto Mirela Sangoi, Rosa Ricardo Abreu da, Santini Manuela Favarin, Cavenago Bruno Cavalini, Duarte Marco Antônio Húngaro, Bier Carlos Alexandre Souza, Só Marcos Vinícius Reis
Department of Stomatology, Federal University of Santa Maria, Santa Maria, RS, Brazil.
Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
J Appl Oral Sci. 2016 Jan-Feb;24(1):37-44. doi: 10.1590/1678-775720150090. Epub 2015 Jul 21.
The aim of this study was to evaluate the volume of remaining filling material after passive ultrasonic irrigation (PUI) of sodium hypochlorite (NaOCl) and orange oil in mesial canals of mandibular molars, with and without isthmus.
Thirty mesial roots of mandibular molars were divided according to the presence or absence of isthmus. Canals were prepared and filled (Micro-CT #1). Filling was removed using rotary instruments, and specimens were sub-divided into three groups according to the irrigation procedures: Conventional - conventional irrigation with NaOCl, PUI/NaOCl - PUI of NaOCl (three activations, 20 seconds each), and PUI/orange oil - PUI of orange oil (Micro-CT#2). Specimens were enlarged using the X2 and X3 ProTaper Next instruments and submitted to the same irrigation protocols (Micro-CT #3).
No differences were found between the experimental groups in each stage of assessment (P>0.05). The volume of residual filling material was similar to that in Micro-CT #2 and Micro-CT #3, but lower than that observed in Micro-CT #1 (P<0.05). When groups were pooled according to the presence or absence of an isthmus, volume of residual filling material was higher in specimens presenting isthmus (P<0.05).
PUI of NaOCl or orange oil did not improve filling removal. Isthmus consists in an anatomical obstacle that impairs the removal of filling material.
本研究旨在评估在下颌磨牙近中根管中，使用次氯酸钠（NaOCl）和橙油进行被动超声冲洗（PUI）后，有无峡部情况下剩余充填材料的体积。
根据有无峡部将30个下颌磨牙的近中根进行分组。预备并充填根管（微型计算机断层扫描#1）。使用旋转器械去除充填物，然后根据冲洗程序将标本分为三组：传统组——用NaOCl进行传统冲洗，PUI/NaOCl组——对NaOCl进行PUI（三次激活，每次20秒），以及PUI/橙油组——对橙油进行PUI（微型计算机断层扫描#2）。使用X2和X3 ProTaper Next器械扩大标本，并采用相同的冲洗方案（微型计算机断层扫描#3）。
在每个评估阶段，各实验组之间均未发现差异（P>0.05）。残余充填材料的体积与微型计算机断层扫描#2和微型计算机断层扫描#3中的相似，但低于微型计算机断层扫描#1中观察到的体积（P<0.05）。根据有无峡部对各组进行汇总时，有峡部的标本中残余充填材料的体积更高（P<0.05）。
NaOCl或橙油的PUI并不能改善充填物的去除。峡部是阻碍充填材料去除的解剖学障碍。
