Advancing endodontic imaging: a high-resolution comparison between CBCT and micro-CT in the danger zone
DOI:
https://doi.org/10.2340/biid.v13.46618Keywords:
Cone-beam computed tomography, danger zone, endodontics, micro-computed tomography, root canalAbstract
Objective: This study evaluated the accuracy of cone-beam computed tomography (CBCT) protocols for measuring submillimetric dentin thickness in the danger zone (DZ) of mandibular molars, using micro-computed tomography (micro-CT) as the reference standard.
Materials and methods: Fifty-one extracted mandibular molars were scanned using micro-CT and two CBCT devices under different acquisition protocols (Standard, High Fidelity, High Resolution [HIRE], and Imaging System [i-CAT]). After three-dimensional image registration, dentin thickness in the DZ, located 2 mm below the furcation, was measured in both mesial canals.
Results: All CBCT protocols significantly underestimated dentin thickness compared with micro-CT (p < 0.05), with discrepancies ranging from 4.5 to 8.6%. Underestimation was more pronounced in the mesiolingual canal. The HIRE protocol (0.125 mm voxel size) showed the smallest discrepancy, whereas the i-CAT protocol showed the largest.
Conclusion(s): CBCT systematically underestimates dentin thickness in the DZ and is not metrically equivalent to micro-CT for submillimetric measurements. Measurement accuracy is influenced by acquisition parameters and cannot be explained by voxel size alone.
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Copyright (c) 2026 Gabriel de Toledo Telles-Araujo, Raimundo Sales de Oliveira Neto, Mariana Quirino Silveira Soares, Heitor Marques Honório, Viviane Almeida Sarmento, Marco Antônio Hungaro Duarte, Izabel Regina Fischer Rubira-Bullen
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