Applied Health Sciences Post-Graduate Program, Federal University of Juiz de Fora, Minas Gerais, Brazil.
Applied Health Science Post-Graduate Program and Department of Dentistry, Federal University of Juiz de Fora, Minas Gerais, Brazil.
Oral Surg Oral Med Oral Pathol Oral Radiol. 2024 Jun;137(6):662-670. doi: 10.1016/j.oooo.2024.02.007. Epub 2024 Feb 17.
To verify if assessment of the danger zone (DZ) in the mesial root of mandibular molars is affected by field of view (FOV) and voxel sizes in cone beam computed tomography (CBCT) scans.
Forty mandibular molars were scanned by micro-computed tomography, creating the reference standard. The teeth were then submitted for CBCT scans with FOVs of 10 × 5.5 cm and 5 × 5.5 cm and voxel sizes of 0.4, 0.2, 0.15, and 0.075 mm. The smallest dentin thickness in the DZ from the mesiobuccal and mesiolingual canals was measured at 2, 4, and 6 mm apical to the root furcation. Descriptive statistics, paired t-tests, and intraclass correlation coefficients were used for statistical analysis with significance established at P < .05.
All CBCT measurements overestimated the DZ dentin thickness (P < .001) compared to the reference standard. The greatest overestimation occurred in the 5 × 5.5 cm FOV with 0.4 mm voxels (P = .007). Dentin thickness measured with the 5 × 5.5 cm FOV and 0.075 mm voxels was significantly smaller and produced the best ICC value with the reference standard (0.936).
CBCT overestimates the dentin thickness of the DZ regardless of FOV and voxel sizes. The 5 × 5.5 cm FOV showed the best performance with the 0.075 mm voxel size, but it performed poorly with 0.4 mm voxels.
验证在锥形束计算机断层扫描（CBCT）扫描中，视场（FOV）和体素大小是否会影响下颌磨牙近中根的危险区（DZ）的评估。
对 40 颗下颌磨牙进行微计算机断层扫描，创建参考标准。然后将这些牙齿进行 CBCT 扫描，FOV 分别为 10×5.5cm 和 5×5.5cm，体素大小分别为 0.4mm、0.2mm、0.15mm 和 0.075mm。在根分叉上方 2、4 和 6mm 处，测量近颊和近舌根管的 DZ 内最小牙本质厚度。采用描述性统计、配对 t 检验和组内相关系数进行统计分析，以 P<0.05 为差异有统计学意义。
与参考标准相比，所有 CBCT 测量值均高估了 DZ 牙本质厚度（P<0.001）。在 0.4mm 体素的 5×5.5cm FOV 中，高估程度最大（P=0.007）。在 5×5.5cm FOV 和 0.075mm 体素下测量的牙本质厚度明显更小，与参考标准的 ICC 值最高（0.936）。
无论 FOV 和体素大小如何，CBCT 均高估了 DZ 的牙本质厚度。5×5.5cm FOV 与 0.075mm 体素结合表现最佳，但与 0.4mm 体素结合时表现不佳。
