Ha Se-Won, Choi Stephanie M, Kim Sunil, Song Minju, Hu Kyung-Seok, Kim Euiseong
Department of Conservative Dentistry and Oral Science Research Center, Microscope Center, Yonsei University College of Dentistry, Seoul, Korea.
Department of Conservative Dentistry, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
Int Endod J. 2025 Feb;58(2):295-304. doi: 10.1111/iej.14161. Epub 2024 Nov 4.
Despite the high success rate of endodontic microsurgery (EMS), it is difficult to suggest EMS as a general treatment option considering the difficulty of the procedure. A surgical guide has been proposed to overcome this problem. This study aimed to evaluate the stability of the surgical guide of a new design concept, as well as the accuracy of root resection, and to introduce the manufacturing method of the newly designed surgical guide.
The experiment was conducted on 59 roots (9 in the maxillary and 50 in the mandibular region) of adult human cadavers. The surgical guide was designed using CAD/CAM design software based on cone-beam computed tomography (CBCT) images and optical scan files. Unlike conventional surgical guides, the surgical guide proposed herein was designed to act as a tooth-bone-supported removable appliance. Two different types of guides were prepared: the osteotomy guide (O guide) for separation of the cortical bone above the root tip with a trephine bur with an outer diameter of 6 mm and the root resection guide (R guide) for resection of the root tip with a trephine bur with an outer diameter of 4 mm. For stability evaluation, the guides were pressed at five predetermined locations after installation and checked for the presence of any movement. For accuracy evaluation, the length at which the root tip was cut was measured and examined by overlapping the preoperative and postoperative CBCT images.
Of the 15 R guides, 14 were stably installed without mobility. For the R guide group, the root tip was resected with an average of 3.2 mm, showing better results than the no-guide group with an average of 4.0 mm.
The newly designed surgical guide of this study can be applied more stably, enabling root resection to be performed more accurately and simply according to the preoperative plan than when performed without a guide.
尽管牙髓显微外科手术（EMS）成功率较高，但鉴于该手术操作难度，很难将其作为一种常规治疗选择。已提出一种手术导板来解决这一问题。本研究旨在评估一种新设计概念的手术导板的稳定性以及根尖切除的准确性，并介绍新设计手术导板的制造方法。
对成人尸体的59颗牙根（上颌9颗，下颌50颗）进行实验。基于锥形束计算机断层扫描（CBCT）图像和光学扫描文件，使用CAD/CAM设计软件设计手术导板。与传统手术导板不同，本文提出的手术导板设计为牙-骨支撑的可摘装置。制备了两种不同类型的导板：用于用外径6mm的环钻分离根尖上方皮质骨的截骨导板（O导板）和用于用外径4mm的环钻切除根尖的根尖切除导板（R导板）。为评估稳定性，安装后在五个预定位置按压导板，检查是否有移动。为评估准确性，测量根尖切除长度，并通过术前和术后CBCT图像重叠进行检查。
15个R导板中，14个稳定安装，无移动。对于R导板组，根尖平均切除3.2mm，比无导板组平均4.0mm的效果更好。
本研究新设计的手术导板应用更稳定，与无导板操作相比，能使根尖切除更准确、更简单地按照术前计划进行。
