Influence of voxel size on dentinal microcrack detection by micro-CT after root canal preparation

Author(s)

Pinto, Jader Camilo ; Coaguila-Llerena, Hernan ; Esteves Torres, Fernanda Ferrari ; Lucas-Oliveira, Everton ; Bonagamba, Tito Jose ; Guerreiro-Tanomaru, Juliane Maria ; Tanomaru-Filho, Mario

• Document type: Journal article
• Source: BRAZILIAN ORAL RESEARCH; v. 35, p. 8-pg., 2021-01-01.

Abstract

The aim of this study was to assess the influence of microcomputed tomography (micro-CT) voxel size on dentinal microcrack detection after root canal preparation using rotary heat-treated nickeltitanium files. Curved mesial root canals (n = 24) of mandibular molars were prepared using ProDesign Logic 30/.05 (PDL) or HyFlex EDM 25/.08 (HEDM). The specimens were scanned by micro-CT at 5 mu m voxel size before and after root canal preparation. The percentage of microcracks was evaluated in images at 5, 10 and 20 mu m voxel size, by two examiners at two moments. The Kappa and McNemar tests (a = 0.05) were used. The percentage of dentinal microcracks was similar before and after PDL and HEDM preparations, at 10 and 20 mu m (p > 0.05). HEDM showed a higher percentage of dentinal microcracks in the middle third at 5 mu m after preparation (p < 0.05). The detection of dentinal microcracks before and after instrumentation using PDL was more accurate at 5 mu m than at 20 mu m, in all thirds (p < 0.05). Within the limitations of this ex vivo study, as expected, the results showed that different resolutions influence the micro-CT analysis of microcracks. The highest accuracy in detecting microcracks was observed for analyses performed at 5 mu m voxel size. HyFlex EDM caused even more microcracks to develop in the middle third, detectable only by visualization of images made at 5 mu m voxel size. (AU)

• FAPESP's process: 18/19665-6 - Effect of the acquisition and analysis of the images in micro-CT in the evaluation of different phases of endodontic treatment in mandibular molars
• Grantee: Jáder Camilo Pinto
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/22885-0 - Evaluation of root fractures in different CBCT devices using different parameters and detections of dentinal microcracks by nano-CT
• Grantee: Jáder Camilo Pinto
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate