Hülsmann M, Stotz S
Department of Operative Dentistry, Zentrum ZMK, University of Göttingen, Germany.
Int Endod J. 1997 Jul;30(4):227-33. doi: 10.1046/j.1365-2591.1997.00036.x.
The purpose of this study was to evaluate the efficacy, cleaning ability and safety of five different devices and techniques to remove gutta-percha root canal fillings. One hundred and twenty extracted single-rooted anterior and premolar teeth were enlarged to ISO size 35 and obturated with laterally condensed gutta-percha using AH 26 as the sealer. Removal of gutta-percha was performed with the following devices and techniques: (a) Gates-Glidden and Hedstrom files, (b) only Hedstrom files, (c) Hedstrom files and chloroform, (d) the Endotec and Hedstrom files, and (e) the XGP drill and Hedstrom files. The following data were recorded: time taken to reach the desired working length, time required for the removal of the gutta-percha, and the amount of material extruded apically. The teeth were split longitudinally and photographed. Cleanliness of the root canal walls was scored using the projected slides with a total magnification of approximately 70x. The fastest technique to reach the working length was using the XGP drill (e), followed by the Gates-Glidden drills (a), Hedstrom files and chloroform (c), and the Endotec device (d). The use of Hedstrom files (b) without any additional support proved to be most time-consuming. Differences were statistically significant (U-test, P > 0.05) between the rotary devices and the manual techniques. Time for complete removal of gutta-percha was again shortest with the XGP drills (e), followed by the Gates-Glidden burs (a), the Endotec device (d), Hedstrom files with chloroform (c), and Hedstrom files alone (b). The XGP burs and the Gates-Glidden drills worked significantly faster than the other techniques. The amount of debris and filling material extruded apically in most cases did not exceed 0.1 mg. No significant differences could be detected between the groups (U-test, P > 0.05). Root canal cleanliness proved best following the use of Hedstrom files without additional support (b) and the Gates-Glidden drills (a), followed by Hedstrom files in combination with chloroform (c), the XGP-gutta-percha remover (e), and the Endotec device (d). When using the XGP two instrument fractures occurred in the apical parts of the root canals preventing further instrumentation to the apical foramen. When using the Gates-Glidden burs four instrument fractures occurred, but all fragments could be removed with forceps immediately. The results suggest that the XGP gutta-percha remover and the Gates-Glidden drills are efficient and time saving devices to remove gutta-percha but include a certain risk of instrument breakage and may leave some filling material inside the root canal. The best root canal cleanliness was achieved with Hedstrom files alone which, on the other hand, were shown to be the most time-consuming.
本研究的目的是评估五种不同器械和技术去除牙胶根管充填物的有效性、清洁能力及安全性。选取120颗拔除的单根前牙和前磨牙，将根管扩大至ISO 35号，使用AH 26作为封闭剂，采用侧向加压法充填牙胶。使用以下器械和技术去除牙胶：(a) 盖茨 - 格利登锉和赫斯特勒姆锉；(b) 仅使用赫斯特勒姆锉；(c) 赫斯特勒姆锉和氯仿；(d) Endotec器械和赫斯特勒姆锉；(e) XGP钻和赫斯特勒姆锉。记录以下数据：达到理想工作长度所需时间、去除牙胶所需时间以及根尖部挤出的材料量。将牙齿纵向劈开并拍照。使用总放大倍数约为70倍的投影幻灯片对根管壁清洁度进行评分。达到工作长度最快的技术是使用XGP钻（e），其次是盖茨 - 格利登钻（a）、赫斯特勒姆锉和氯仿（c）以及Endotec器械（d）。事实证明，仅使用赫斯特勒姆锉（b）且无任何辅助时最为耗时。旋转器械与手动技术之间的差异具有统计学意义（U检验，P>0.05）。使用XGP钻（e）时，完全去除牙胶的时间再次最短，其次是盖茨 - 格利登车针（a）、Endotec器械（d）、含氯仿的赫斯特勒姆锉（c）以及仅使用赫斯特勒姆锉（b）。XGP车针和盖茨 - 格利登钻的工作速度明显快于其他技术。在大多数情况下，根尖部挤出的碎屑和充填材料量不超过0.1毫克。各组之间未检测到显著差异（U检验，P>0.05）。事实证明，仅使用赫斯特勒姆锉（b）和盖茨 - 格利登钻（a）后根管清洁度最佳，其次是赫斯特勒姆锉与氯仿联合使用（c）、XGP牙胶去除器（e）以及Endotec器械（d）。使用XGP时，在根管根尖部发生了两起器械折断，妨碍了进一步向根尖孔的器械操作。使用盖茨 - 格利登车针时发生了四起器械折断，但所有碎片均可立即用镊子取出。结果表明，XGP牙胶去除器和盖茨 - 格利登钻是去除牙胶的高效省时器械，但存在一定的器械折断风险，且可能在根管内残留一些充填材料。仅使用赫斯特勒姆锉可实现最佳的根管清洁度，然而，其最为耗时。
