Digital Visual Assessment of Tooth Wear: Practical Comparison of BEWE, Simplified TWI and TWES 2.0 on Intraoral Scans...

Objectives: This study aimed to evaluate and compare the performance of three tooth wear indices-BEWE, simplified TWI (sTWI), and TWES 2.0-based on the visual assessment of digital intraoral scans. A secondary exploratory objective was to examine unadjusted sex-stratified score distributions. Methods: This retrospective study included 246 anonymized intraoral scans obtained using Medit i700 and iTero Element 2 systems. All scans were independently evaluated by two calibrated examiners using the BEWE, simplified TWI (sTWI), and TWES 2.0 indices. Scoring was performed through visual assessment of the digital models, without applying automated measurements or software-assisted analysis tools. Unadjusted sex-stratified patterns were explored using mixed-effects linear models, with a significance threshold set at p < 0.05. Estimated marginal means were calculated, and graphical approaches, including heatmaps, were used to present score distributions and inter-examiner variability. Results: The indices exhibited different scoring characteristics. BEWE produced the most consistent sextant-based patterns, with low variability between examiners. TWES 2.0 showed generally stable scoring, although with slightly greater dispersion, particularly in posterior sextants. In contrast, sTWI demonstrated the highest variability and more pronounced surface-specific differences, especially on occlusal and palatal surfaces. Sex-stratified analyses indicated minor and inconsistent variations. Although isolated statistically significant findings were observed (BEWE Sextant 6; TWES 2.0 Sextant 5), they did not form a consistent or interpretable pattern. Conclusions: Assessment based on digital intraoral scans highlighted differences in scoring behavior depending on the index used. BEWE demonstrated the most stable scoring patterns, TWES 2.0 showed moderate consistency, while sTWI was associated with the greatest variability. Differences observed in sex-stratified analyses were minor and lacked consistency. Clinical significance: BEWE enables consistent scoring when applied to digital scans and may be appropriate for monitoring purposes. TWES 2.0 provides a structured approach to screening. The higher variability observed with sTWI indicates that caution is warranted when it is used exclusively on digital models. Overall, the choice of index has a substantial impact on the assessment of tooth wear in digital workflows.