Preetam C S, Chandrashekhar M, Gunaranjan T, Kumar S Kishore, Miskeen Sahib S A, Kumar M Senthil
Department of Conservative Dentistry and Endodontics, Madha Dental College, Chennai, Tamil Nadu, India.
Department of Conservative Dentistry and Endodontics, G. Pulla Reddy Dental College, Kurnool, India.
J Int Soc Prev Community Dent. 2016 Aug;6(Suppl 2):S131-6. doi: 10.4103/2231-0762.189740.
The purpose of this study is to achieve an effective method to remove root canal filling material from the root canal system. The study, thus, aims to evaluate the efficacy of the cleaning ability of two different rotary Ni-Ti systems; ProTaper Retreatment files and RaCe System compared to hand instrumentation with Hedstrom files for the removal of gutta-percha during retreatment.
Thirty mandibular premolars with one single straight canal were decoronated and instrumented with ProTaper files and filled with thermoplastic gutta-percha. After 30 days, the samples were divided into three groups and gutta-percha was removed with the test instruments. The postoperative radiographs were evaluated with known criteria by dividing the root into cervical third, middle third, and apical third. The results were tabulated and Statistical Package for Social Sciences Software (IBM Corporation) was used for analysis.
The mean deviation of the results were first calculated and then t-test and analysis of variance test (two-tailed P value) were evaluated for establishing significant differences. The rotary instruments were effective in removing the gutta-percha from the canals. Therefore, significant difference was observed between the efficacies of the two rotary systems used. The rotary instruments showed effective gutta-percha removal in the cervical and middle one third. (P > 0.05). However, apical debridement was effective with Hedstrom files.
The study concluded the use of both rotary and hand instrumentation for effective removal of gutta-percha for retreatment.
本研究的目的是找到一种从根管系统中去除根管充填材料的有效方法。因此，该研究旨在评估两种不同的旋转镍钛系统；ProTaper再治疗锉和RaCe系统与使用Hedstrom锉进行手动器械预备在再治疗期间去除牙胶的清洁能力的疗效。
选取30颗具有单一直根管的下颌前磨牙，截冠后用ProTaper锉进行预备，并用热塑性牙胶充填。30天后，将样本分为三组，使用测试器械去除牙胶。术后根尖片根据已知标准进行评估，将牙根分为颈段、中段和根尖段。结果制成表格，并使用社会科学统计软件包（IBM公司）进行分析。
首先计算结果的平均偏差，然后进行t检验和方差分析（双侧P值）以确定是否存在显著差异。旋转器械在从根管中去除牙胶方面是有效的。因此，观察到所使用的两种旋转系统的疗效之间存在显著差异。旋转器械在颈段和中段三分之一处显示出有效的牙胶去除效果。（P>0.05）。然而，根尖清创使用Hedstrom锉是有效的。
该研究得出结论，使用旋转器械和手动器械预备均可有效去除牙胶以进行再治疗。
