Abstract：
Objective: This study aimed to evaluate the effectiveness of photon-induced photoacoustic streaming (PIPS), XP-endo Finisher (XPF), and passive ultrasonic irrigation (PUI) for the removal of root canal filling materials from oval root canals. Background: Various adjunctive irrigation techniques following mechanical preparation have been applied to enhance removal of fillings during root canal retreatment. However, whether there is superiority of one approach over others remains controversial. Methods: Thirty extracted single-rooted teeth with oval-shaped canals were instrumented with the ProTaper Next (PTN) system and obturated with the warm vertical compaction technique. After storage at 37°C for 1 month, retreatment was performed with the PTN system up to size X4. The teeth were then randomly assigned into three groups (n = 10) that were, respectively, subjected to supplementary irrigation with different protocols: PIPS, PUI, and XPF, followed by measurement of filling material volumes using high-resolution micro-computed tomography. Results: The PTN preparation resulted in significant reductions in residual filling materials (p < 0.05), whereas PIPS, PUI, and XPF moderately improved the removal of the remnants (p > 0.05). The residual filling materials after supplementary irrigation ranged from 0.384 ± 0.181 to 0.421 ± 0.143 mm3 in oval canals. There was no significant difference in the effectiveness among the PIPS, PUI, and XPF approaches (p > 0.05). Conclusions: Mechanical preparations are useful for removing most root fillings during retreatment in oval-shaped canals. PIPS can reduce residual root-filling materials to the similar extent as PUI and XPF.
摘要：
目的:本研究旨在评估光子诱导光声流(PIPS)的有效性,XP-endoFinisher(XPF),和被动超声冲洗（PUI），用于从椭圆形根管中去除根管填充材料。背景：机械准备后的各种辅助冲洗技术已被用于增强根管再治疗过程中填充物的去除。然而,一种方法是否优于其他方法仍然存在争议。方法：用ProTaperNext（PTN）系统对30颗带有椭圆形运河的单根牙齿进行仪器安装，并用热垂直压实技术进行封闭。在37°C下储存1个月后，用最大尺寸X4的PTN系统进行再处理。然后将牙齿随机分为三组（n=10），分别,接受不同协议的补充灌溉：PIPS，PUI,和XPF，然后使用高分辨率微型计算机断层扫描测量填充材料的体积。结果：PTN制剂导致残留填充材料的显着减少（p<0.05），而PIPS,PUI,XPF和XPF适度改善了残留物的去除（p>0.05）。补充灌溉后的剩余填充材料在椭圆形运河中的范围为0.384±0.181至0.421±0.143mm3。PIPS之间的有效性没有显着差异，PUI,和XPF方法(p>0.05)。结论：机械制剂可用于在椭圆形管的再治疗过程中去除大部分牙根填充物。PIPS可以与PUI和XPF相似地减少残留的根填充材料。
