25 Years Clinical Evaluation of Tooth Wear: a 3D Methodology

Objectives: This in vivo study aimed to quantitatively evaluate the progression of tooth wear and noncarious cervical lesions (NCCLs) by superimposing premolars into three-dimensional (3D) digital models over a 25-year follow-up period.
Methods: Thirty-three participants were included in this retrospective observational study. Impressions were taken at two-time points: Phase I (1996) and Phase III (2021). The corresponding dental casts were scanned to generate digital 3D models. Using 3D analysis software (Geomagic Control X 2020.1; 3D Systems), the premolars were analyzed. To assess occlusal tooth wear, the premolars from Phase II were individually segmented and superimposed onto their Phase I equivalents using the best-fit method, with the crowns serving as the reference area. Volume loss for each occlusal premolar was quantified using the 3D comparison tool. For NCCL assessment, height, depth, width, and area measurements were performed. Descriptive statistical analyses were conducted to evaluate the findings.
Results: The mean volume of tooth wear in maxillary premolars was 0.028 ± 0.006 mm, and for mandibular premolars, it was 0.021 ± 0.014 mm after 25 years. The root mean square (RMS) deviation for maxillary premolars was 0.117 mm, while for mandibular premolars, it was 0.120 mm. For NCCL volume loss evaluation, 11.3% of maxillary premolars exhibited lesions greater than 2 mm, and 10.3% of mandibular premolars showed lesions with similar depth.
Conclusions: Three-dimensional digital models and regional registration techniques provide a reliable and precise method for evaluating tooth wear and NCCL progression over extended periods. This approach allows for a detailed quantitative analysis, offering valuable insights into long-term changes in tooth morphology.