The primary aim of this study was to compare mesiodistal tooth-width measurements and Bolton analysis outputs generated by three orthodontic software platforms (3Shape OrthoAnalyzer®, uDesign®, and Titan Dental Design™) against a physical caliper control. The study utilized pre- and post-treatment digital models from patients with mild to moderate crowding. The secondary aim of this study was to assess the effect of mild to moderate crowding on the accuracy of mesiodistal tooth-width measurements of these same three orthodontic software platforms.

A retrospective analysis was conducted using de-identified pre- and post-treatment digital models from 14 orthodontic patients with mild to moderate crowding treated at Louisiana State University School of Dentistry. All models were acquired via intraoral scanning and processed through each platform's automated segmentation workflow. Physical control models were 3D printed from the same STL files and measured with a digital caliper. Linear mixed-effects models with Tukey-adjusted pairwise comparisons were used for statistical analysis.

Mesiodistal tooth-width measurements differed significantly among all three platforms ( P < 0.05), as did platform-specific deviations from the physical control. Titan Dental Design™ demonstrated the greatest overestimation relative to the physical reference, while 3Shape OrthoAnalyzer® most closely approximated caliper measurements. All inter-software differences remained below the predetermined 0.25 mm clinical significance threshold. Significant differences in overall Bolton ratios were identified at pretreatment but not at post-treatment. It was also found that tooth alignment did not significantly influence measurement accuracy.

Statistically significant but subclinical differences exist among orthodontic software platforms in mesiodistal tooth-width measurements and Bolton analyses. Clinicians are encouraged to maintain consistency in platform use and exercise informed judgment when interpreting software-generated Bolton analyses, particularly for overall ratios and posterior teeth.