Influence of Cone-Beam Computed Tomography Voxel Size on the Accuracy of Periodontal Ligament Surface Area Measurements.

Objective: Accurate assessment of the periodontal ligament (PDL) is critical for developing effective treatment plans in periodontics, orthodontics, prosthodontics, and maxillofacial surgical. This study aimed to investigate the influence of cone-beam computed tomography (CBCT) voxel size (0.3 and 0.1 mm) on the accuracy of PDL surface area measurements.

Methods: Thirty-nine teeth, including both single-rooted and multirooted types, were obtained from 5 human skulls and imaged using CBCT and high-resolution computed tomography (CT). The PDL was segmented and reconstructed using Mimics and 3-matic software to determine surface area measurements. Statistical analyses included paired t tests (P<0.05) to identify significant differences and Bland-Altman plots to evaluate agreement between measurements obtained at different voxel sizes.

Results: Paired t tests demonstrated a statistically significant difference in PDL surface area measurements based on voxel size (t=4.959, P=0.001). Bland-Altman analysis revealed that measurements obtained with a voxel size of 0.1 mm were, on average, 5.07 mm² larger than those obtained with a voxel size of 0.3 mm.

Conclusions: Voxel size significantly affects the precision of PDL surface area measurements, with smaller voxels yielding greater surface detail and higher surface area values. High-resolution CT provided more accurate and reliable measurements of PDL surface area compared with CBCT.