Guedes Orlando Aguirre, Ferreira Henrique Carneiro, Abreu Danielly Moreira, de Lima Kássia Sousa, Souza Esther Menezes, de Freitas Yasmin Gomes, Decurcio Daniel de Almeida, Estrela Carlos
Department of Endodontics, School of Dentistry, Evangelical University of Goiás, Anápolis, GO, Brazil.
Department of Stomatology Sciences, School of Dentistry, Federal University of Goiás, Goiânia, GO, Brazil.
J Clin Exp Dent. 2025 Feb 1;17(2):e195-e203. doi: 10.4317/jced.62524. eCollection 2025 Feb.
This study aimed to evaluate the impact of different gutta-percha removal (GPR) techniques on the occurrence of dentinal defects in bovine root canals.
One hundred and eight bovine incisors were selected and stored in distilled water. The crowns were removed, leaving roots approximately 17 mm in length. Twelve roots were left unprepared and served as control (G1), and the remaining 96 roots were instrumented with BioRace files up to size 40/.04 (BR5) and filled with gutta-percha and Sealapex sealer using the lateral condensation technique. Twelve other roots were left filled and received no retreatment procedure (G2). The remaining 84 roots underwent filling material removal with R-Endo (G3), D-Race (G4), WaveOne Gold (G5), ProTaper Retreatment (G6), Mtwo R (G7), Reciproc (G8) instruments or with R1-Clearsonic ultrasonic insert (G9). After GPR, final apical enlargement was achieved using a BR7 (#60/.02) instrument. Roots were sectioned 3, 6 and 9 mm from the apex and observed under a stereomicroscope at 25ᵡ magnification. The presence/absence of root fractures, microcracks, and craze lines were recorded. Chi-square tests compared the incidence of dentinal defects between the groups, with a significance level set at <.05.
Defects occurred in 46.6% of the samples. No defects were observed in the unprepared canals (control, G1). Defects were detected in all other experimental groups (G2 to G9). Among retreatment techniques the R-Endo group (G3) presented significantly higher microcracks and craze lines (<.05). Defects were more frequent in the coronal and middle thirds.
All GPR methods were linked to dentinal defects. The R-Endo system significantly increased microcracks and craze lines. Cracks, Dentinal defects, Gutta-percha removal, Retreatment, Vertical root fracture.
本研究旨在评估不同的根管牙胶去除（GPR）技术对牛根管牙本质缺损发生情况的影响。
选取108颗牛切牙并保存在蒸馏水中。去除牙冠，保留长度约为17mm的牙根。12个牙根未做处理作为对照（G1），其余96个牙根用BioRace锉预备至40/.04号（BR5），采用侧向加压技术用牙胶和Sealapex封闭剂充填。另外12个牙根充填后未进行再治疗操作（G2）。其余84个牙根分别用R-Endo（G3）、D-Race（G4）、WaveOne Gold（G5）、ProTaper再治疗（G6）、Mtwo R（G7）、Reciproc（G8）器械或R1-Clearsonic超声插入器（G9）去除充填材料。GPR后，用BR7（#60/.02）器械完成最终根尖扩大。从根尖3mm、6mm和9mm处将牙根切片，在25倍放大率的体视显微镜下观察。记录牙根骨折、微裂纹和裂纹线的有无。采用卡方检验比较各组牙本质缺损的发生率，显著性水平设定为<.05。
46.6%的样本出现缺损。未预备的根管（对照组，G1）未观察到缺损。在所有其他实验组（G2至G9）均检测到缺损。在再治疗技术中，R-Endo组（G3）出现微裂纹和裂纹线的比例显著更高（<.05）。缺损在冠部和中三分之一处更常见。
所有GPR方法均与牙本质缺损有关。R-Endo系统显著增加了微裂纹和裂纹线。裂纹、牙本质缺损、牙胶去除、再治疗、垂直牙根骨折。
