Diagnóstico de fraturas verticais mésio-distais em dentes com pino metálico: influência da aplicação de filtros em imagens de TCFC de diferentes resoluções

Abstract

The aim of this study was to evaluate the influence of applying filters in cone beam computed tomography (CBCT) images at different resolutions. These CBCT images were obtained for diagnosing mesiodistal vertical root fractures (VRF) in teeth with metal posts. Forty teeth were treated endodontically, and twenty received metal posts. Ten teeth without posts and ten teeth with posts were subjected to VRF in the mesiodistal direction. The sample was submitted to periapical radiographs and CBCT exams with a voxel of 0.25 and 0.30 mm. In order to reduce the influence of the metal artifact in the CT images, the teeth were evaluated with and without the application of filters ("Sharpen" and "Hard"). The images were evaluated by two radiologists who had to identify the presence of VRF. Accuracy values (ROC curves) for the different variables were compared using an analysis of variance and t-test. No difference was observed between images with and without filter application (p = 0.860). Images obtained with a 0.25 mm voxel were more accurate (p = 0.001). The presence of the metal post reduced the accuracy of the diagnosis of VRF (p = 0.001), and the CT images showed superior results compared to periapical radiographs (p = 0.005). It can be concluded that the presence of a metal post and the voxel size significantly interfere with the diagnosis of VRF. Independent of the formation of metal artifacts associated with metallic cores, applying filters did not improve the diagnosis. For mesiodistal VRF, the CBCT images are superior to the periapical radiographs.