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

Author(s)

Jáder Camilo PINTO ^[1] ; Hernán COAGUILA-LLERENA ^[2] ; Fernanda Ferrari Esteves TORRES ^[3] ; Éverton LUCAS-OLIVEIRA ^[4] ; Tito José BONAGAMBA ^[5] ; Juliane Maria GUERREIRO-TANOMARU ^[6] ; Mário TANOMARU-FILHO ^[7]

Affiliation

^[1] Universidade Estadual Paulista. School of Dentistry. Department of Restorative Dentistry - Brasil

^[2] Universidade Estadual Paulista. School of Dentistry. Department of Restorative Dentistry - Brasil

^[3] Universidade Estadual Paulista. School of Dentistry. Department of Restorative Dentistry - Brasil

^[4] Universidade de São Paulo. São Carlos Institute of Physics. Department of Physics and Interdisciplinary Science - Brasil

^[5] Universidade de São Paulo. São Carlos Institute of Physics. Department of Physics and Interdisciplinary Science - Brasil

^[6] Universidade Estadual Paulista. School of Dentistry. Department of Restorative Dentistry - Brasil

^[7] Universidade Estadual Paulista. School of Dentistry. Department of Restorative Dentistry - Brasil

• Document type: Journal article
• Source: Brazilian Oral Research; v. 35, 2021-10-11.

Abstract

Abstract The aim of this study was to assess the influence of micro-computed tomography (micro-CT) voxel size on dentinal microcrack detection after root canal preparation using rotary heat-treated nickel-titanium 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 μm voxel size before and after root canal preparation. The percentage of microcracks was evaluated in images at 5, 10 and 20 μm voxel size, by two examiners at two moments. The Kappa and McNemar tests (α = 0.05) were used. The percentage of dentinal microcracks was similar before and after PDL and HEDM preparations, at 10 and 20 μm (p > 0.05). HEDM showed a higher percentage of dentinal microcracks in the middle third at 5 μm after preparation (p < 0.05). The detection of dentinal microcracks before and after instrumentation using PDL was more accurate at 5 μm than at 20 μm, 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 μm voxel size. HyFlex EDM caused even more microcracks to develop in the middle third, detectable only by visualization of images made at 5 μm 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
• FAPESP's process: 17/19049-0 - Evaluation of the root canal treatment procedures, physicochemical and biological properties of tricalcium silicate-based materials
• Grantee: Mario Tanomaru Filho
• Support Opportunities: Regular Research Grants