Division of Oral Radiology, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
Department of Stomatology, Public Oral Health, and Forensic Dentistry School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
J Endod. 2017 Oct;43(10):1668-1673. doi: 10.1016/j.joen.2017.04.003. Epub 2017 Jun 30.
There is no consensus about the accuracy of cone-beam computed tomography (CBCT) for detecting vertical root fractures (VRFs), nor is there certainty about the isolated effect of different tube current parameters on the diagnosis of VRF through CBCT scans. This study aimed to evaluate how tube current affects the detection of VRF on CBCT examinations in the absence of intracanal materials and in the presence of gutta-percha (GP) and metal (MP) or fiberglass (FP) intracanal posts.
The sample consisted of 320 CBCT scans of tooth roots with and without VRF divided into 8 groups: no fracture/no intracanal material; no fracture + GP; no fracture + MP; no fracture + FP; fracture/no intracanal material; fracture + GP; fracture + MP; fracture + FP. The scans were acquired with an OP300 unit using 4 different milliamperes (4 mA, 8 mA, 10 mA, 13 mA). Five oral radiologists analyzed the images. The area under the receiver operating characteristic curve (Az), sensitivity, specificity, positive and negative predictive values, and interobserver agreement were calculated.
Diagnostic performance for the different milliamperes tested was similar for teeth without root filling materials or with FP. Teeth with GP and MP showed the highest Az values for 8 mA and 10 mA, respectively. For teeth with MP, specificity was significantly higher when 10 mA was used.
For teeth without root filling materials or with FP, the use of a reduced milliampere does not seem to influence the detection of VRF in a significant manner. For teeth with GP and MP, an increased milliampere may lead to increased diagnostic performance.
对于使用锥形束计算机断层扫描（CBCT）检测垂直根折（VRF）的准确性，目前尚无共识，也不确定不同管电流参数对 CBCT 扫描诊断 VRF 的单独影响。本研究旨在评估在没有根管内材料以及存在牙胶（GP）、金属（MP）或玻璃纤维（FP）根管内桩的情况下，管电流如何影响 CBCT 检查中 VRF 的检测。
样本由 320 个有或无 VRF 的牙根 CBCT 扫描组成，分为 8 组：无骨折/无根管内材料；无骨折+GP；无骨折+MP；无骨折+FP；骨折/无根管内材料；骨折+GP；骨折+MP；骨折+FP。使用 OP300 设备以 4 种不同毫安（4mA、8mA、10mA、13mA）采集扫描。5 名口腔放射科医生分析图像。计算受试者工作特征曲线下面积（Az）、敏感性、特异性、阳性和阴性预测值以及观察者间一致性。
对于无根管内材料或 FP 的牙齿，不同毫安测试的诊断性能相似。对于 GP 和 MP 牙，8mA 和 10mA 时 Az 值最高。对于 MP 牙，使用 10mA 时特异性显著提高。
对于无根管内材料或 FP 的牙齿，使用较低毫安似乎不会显著影响 VRF 的检测。对于 GP 和 MP 牙，增加毫安可能会提高诊断性能。
