Rodrigues Clarissa Teles, Jacobs Reinhilde, Vasconcelos Karla Faria, Lambrechts Paul, Rubira-Bullen Izabel Regina Fisher, Gaêta-Araujo Hugo, Oliveira-Santos Christiano, Duarte Marco Antonio Hungaro
Department of Restorative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, São Paulo, Brazil.
Department of Imaging and Pathology, Faculty of Medicine, OMFS IMPATH Research Group, KU Leuven, Leuven, Belgium.
Dentomaxillofac Radiol. 2021 Jul 1;50(5):20200503. doi: 10.1259/dmfr.20200503. Epub 2021 Jan 5.
To evaluate the influence of artefacts in cone beam CT (CBCT) images of filled root canals in isthmus-containing molars.
10 teeth presenting canals with an isthmus were instrumented and filled with a thermoplasticised obturation technique. The teeth were scanned using a micro-CT device and two CBCT devices: 3D Accuitomo 170 (ACC) and NewTom VGi evo (NT), with different acquisition protocols: larger and smaller voxel size. Three examiners assessed the CBCT images for: (1) detection of filling voids; (2) assessment of under- or overestimation of the filling material and (3) resemblance of CBCT images to the reference standard. Analyses of Task 1 yielded accuracy, sensitivity and specificity for detection of filling voids. For tasks 2 and 3, statistical analysis was performed using Wilcoxon test. The level of significance was set at < .05.
For Task 1, ACC showed higher sensitivity, whereas NT presented higher specificity. No significant difference was found between the protocols in ACC, however, for NT, differences between protocols were significant for all diagnostic values. In Task 2, visualisation of the filling was overestimated for NT, while for ACC, underestimation was observed. For Task 3, images with smaller voxel size were more similar to the reference image, for both CBCT devices.
Different artefacts compromise the detection of filling voids on CBCT images of canals in mandibular molars with isthmus. ACC and NT present rather similar diagnostic accuracy, even though artefact expression remains device-specific.
评估伪影对含峡部磨牙根管充填后锥束CT（CBCT）图像的影响。
选取10颗存在峡部根管的牙齿，采用热塑充填技术进行根管预备和充填。使用微型CT设备以及两台CBCT设备（3D Accuitomo 170（ACC）和NewTom VGi evo（NT））对牙齿进行扫描，采用不同的采集协议：较大和较小的体素尺寸。三名检查者对CBCT图像进行评估，内容包括：（1）检测充填体中的空隙；（2）评估充填材料的低估或高估情况；（3）CBCT图像与参考标准的相似性。任务1的分析得出了检测充填体空隙的准确性、敏感性和特异性。对于任务2和3，使用Wilcoxon检验进行统计分析。显著性水平设定为<0.05。
对于任务1，ACC显示出更高的敏感性，而NT具有更高的特异性。ACC的不同协议之间未发现显著差异，然而，对于NT，不同协议之间在所有诊断值上均存在显著差异。在任务2中，NT对充填体的可视化评估过高，而ACC则出现低估。对于任务3，对于两台CBCT设备，较小体素尺寸的图像与参考图像更相似。
不同的伪影会影响对下颌含峡部磨牙根管CBCT图像中充填体空隙的检测。ACC和NT的诊断准确性相当相似，尽管伪影表现仍具有设备特异性。
