锥形束CT应用于下颌第一恒磨牙远中舌根弯曲度的研究

摘要

Objective To measure the curvatures of the distolingual root canals of permanent mandibular first molars by cone-beam computed tomography (CBCT). Methods The CBCT was used to collect 230 cases of mandibular first molar distalingual root from 513 patients. The images were created by 3-D reconstruction based on the BECT data. Images were analyzed by NNT image analysis software. Each tooth was captured in clinical (CV) and proximal view (PV) image, and measured by the Schneider method. Results The average curvature of the distallingual canal was (13.27 ± 8.57)° in CV, and (30.96 ± 11.63)° in PV. Most of the distallingual root in the buccolingual view was mild bending or moderate bending , and the proximal view was severe bending. The distal lingual root bending was the most common in the crown third of the root , next in the apical third of the root, in the middle third of the root. Conclusion CBCT is an effective tool for the detection of additional distolingual roots and is a valuable aid for dentists in root canal treatment.%目的：采用锥形束CT（CBCT）研究下颌第一恒磨牙的远中舌根弯曲度。方法：用CBCT观察513例患者选取所获的下颌第一恒磨牙远中舌根（共230例）进行三维重建，使用自导的NNT 图像分析软件，采集牙齿在近远中向和颊舌向的图像。用Schneider法进行弯曲度测量。结果：下颌第一恒磨牙远中舌根的发生率为30．38％。用Schneider法测得远中舌根颊舌向弯曲度为（13．27±8．57）°，近远中向弯曲度为（30．96±11．63）°。远中舌根在颊舌向观上大多为直根管或中度弯曲，邻面观基本为重度弯曲。远中舌根弯曲位置最常见于根中1／3，其次为根尖1／3，最不常见于冠1／3。结论：下颌第一恒磨牙远中舌根发生率高，形态弯曲， CBCT是有效观察下颌磨牙远中舌根形态的工具，为根管治疗提供参考依据。