THE EFFECT OF DIFFERENT RECONSTRUCTION PARAMETERS ON CONE BEAM CT IN THE ASSESSMENT OF TRABECULAR BONE MICROSTRUCTURE AT PLANNED DENTAL IMPLANT SITES

Background:Cone beam computed tomography (CBCT) has become a valuable tool for evaluating trabecular bone
microarchitecture before implant placement. However, CBCT-derived measurements may be influenced by
reconstruction parameters such as voxel size and threshold level, potentially affecting the reliability of clinical
assessments.
Objectives:This study aimed to evaluate the impact of CBCT reconstruction voxel size and threshold values on the
measurement of trabecular bone microstructure to guide accurate image processing and interpretation.
Materials and Methods:Twenty-seven patients underwent CBCT scanning with a standard acquisition voxel size of
75 μm³. The images were reconstructed at voxel sizes of 75, 115, and 150 μm³ to assess the influence of reconstruction
resolution. Additionally, the effect of threshold variation was examined by modifying the global threshold value by
±15%. Trabecular parameters including bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular
number (Tb.N), and trabecular separation (Tb.Sp) were analyzed using CTAnalyser software. Statistical evaluation
was performed using one-way ANOVA with Tukey’s post hoc test (p < 0.05).
Results:Reconstruction voxel size had no significant effect on BV/TV, Tb.Th, or Tb.Sp, but Tb.N differed
significantly between the 75 µm and 150 µm voxel sizes (p = 0.010). In contrast, threshold variation significantly
affected all trabecular parameters (p < 0.001), with all pairwise comparisons showing statistical significance.
Conclusion:While CBCT reconstruction voxel size showed limited influence on trabecular metrics, threshold level
had a major effect on all measured parameters. These findings emphasize the importance of threshold standardization in clinical CBCT analysis.