Division of Oral Radiology, Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas, Av. Limeira, 901, Piracicaba, São Paulo, 13414-903, Brazil.
Orofacial Pathologies, Imaging and Biotherapies Lab, Université de Paris, URP2496, Montrouge, France.
Sci Rep. 2021 Sep 27;11(1):19155. doi: 10.1038/s41598-021-98345-6.
Dose optimisation has been revisited in the literature due to the frequent use of cone beam computed tomography (CBCT). Although the reduction of the field-of-view (FOV) size has shown to be an effective strategy, this indirectly increases the negative effect from the exomass. The aim of this study was to evaluate the diagnostic accuracy of an optimised CBCT protocol in the detection of simulated vertical root fracture (VRF) in the presence of metal in the exomass and/or inside the FOV. Twenty teeth were endodontically instrumented and VRF was induced in half of them. All teeth were individually placed in a human mandible covered with a soft tissue equivalent material, metallic materials were placed at different dispositions in the exomass and/or endomass, and CBCT scans were obtained at two dose protocols: standard and optimised. Five radiologists evaluated the images and indicated the presence of VRF using a 5-point scale. Area under the ROC curve (AUC), sensitivity, and specificity were calculated and compared using ANOVA (α = 0.05). Overall, AUC, sensitivity, and specificity did not differ significantly (p > 0.05) between the dose protocols. In conclusion, optimised dose protocols should be considered in the detection of simulated VRF irrespective of the occurrence of artefacts from metallic materials in the exomass and/or inside the FOV.
由于频繁使用锥形束计算机断层扫描（CBCT），剂量优化在文献中受到了重新审视。尽管减小视野（FOV）大小已被证明是一种有效的策略，但这会间接增加外源性物质的负面影响。本研究旨在评估优化的 CBCT 方案在存在外源性物质和/或 FOV 内金属的情况下检测模拟垂直根折（VRF）的诊断准确性。20 颗牙齿进行了根管器械处理，其中一半诱导产生了 VRF。所有牙齿均单独放置在覆盖软组织等效材料的人类下颌骨中，将金属材料以不同的位置放置在外源性物质和/或内源性物质中，并使用两种剂量方案（标准和优化）获得 CBCT 扫描。五位放射科医生使用 5 分制评估图像并指示 VRF 的存在。使用方差分析（α=0.05）计算并比较 ROC 曲线下的面积（AUC）、敏感性和特异性。总体而言，两种剂量方案之间的 AUC、敏感性和特异性均无显著差异（p>0.05）。结论是，无论外源性物质和/或 FOV 内是否存在金属材料的伪影，都应考虑优化剂量方案来检测模拟 VRF。
