A influência do tamanho do voxel em tomografia computadorizada de feixe cônico na detecção de perfurações radiculares usando um modelo in vitro

• Autor(a) principal: Melo, Helen Cassia Patricia Gomes
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/001300000dct0
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/10740
• topic: Tomografia computadorizada de feixe cônico; Radiografia periapical; Perfuração radicular; Perfuração de furca; Voxel; Cone beam computed tomography; Periapical radiographs; Root perforation; Furcal perforation; Voxel; CIENCIAS DA SAUDE::ODONTOLOGIA::CLINICA ODONTOLOGICA

The aim of this study was to evaluate the influence of different voxel sizes in diagnostic capability beam computed tomography (CBCT) and compare the accuracy of conventional radiography with CBCT in detecting root perforations. Total of 30 intact third molars were simulated in which holes with diameters of 0.7 mm, 1.1 mm and 1.3 mm, realized in three steps. At each step the teeth were subjected to the process of acquiring images of periapical radiographs and CT scans. The periapical radiographs were performed using an apparatus Spectro 70X (Dabi Atlante, Ribeirão Preto, SP, Brazil) with 70 kVp and current 8mA. The CT scans were performed on four different types of equipment and two voxel sizes: i-Cat Cone Beam 3D Imaging System (Imaging Sciences International, Hatfiels, PA, USA) using voxels of 0.2 mm and 0.4 mm; Newton 3G [Dent-X (Elmsford, New York, USA)] with voxels 0.2 mm and 0.4 mm, Kodak 9000 (Eastman Kodak Company, USA) with voxels 0.076 mm and 0.4 mm and the Gendex GX CB 500 [Gendex Dental Systems (Hatfield, PA, USA)] with voxels of 0.2 mm and 0.4 mm. Six observers (three radiologists and three endodontists) evaluated the images separately using a scoring system: 1-change definitely not identified; 2 - probably not change identified; 3 - uncertainty whether the change has been identified or not; 4-change definitely found and 5-amendment probably found. The results were submitted to chi-square (2), and intra-and interobserver agreement was analyzed using Kappa. The level of significance was 5% (p <0,05). The results showed that CBCT had better performance than the conventional radiography for detecting simulated root perforations. Gendex devices, i-Cat and Kodak 9000 performed well with 0.2 mm voxel, but not performed well using the 0.4 mm voxel; Newton 3G performed well with both the 0.2 mm voxel as using the voxel of 0.4 mm can be used in a protocol voxel resolution of 0.4 mm, which combines image quality with less patient exposure to X-rays.