4.AO_841_CI_Etude comparative des mesures dentaires linéaires sur des modèles numériques issus du scanner intra-oral et du CBCT au modèle en plâtre.

Abstract

Objective: to compare the accuracy of linear dental measurements on digital models generated by intraoral scanning and CBCT, using conventional plaster models as the reference.

Materials and Methods: We conducted a comparative and retrospective study in a private orthodontic dental practice in Abidjan. The study included patients with complete records comprising digital models generated by intraoral scanning, CBCT, and conventional plaster models. Exclusion criteria were models with agenesis or missing teeth, as well as teeth with interproximal restorations. Two software programs were used to perform the various dental measurements (mesiodistal and buccolingual diameters), with the level of statistical significance set at p < 0.05.

Results: A total of 3,600 linear dental measurements were recorded on 1,200 teeth. The mean differences in mesiodistal linear measurements were −1.85 mm for CBCT models compared with plaster models and −1.77 mm for STL models compared with plaster models. These differences were statistically significant (p < 5%). In contrast, the mean differences in vestibulolingual linear measurements were −0.58 mm (CBCT vs. plaster) and −0.68 mm (STL vs. plaster), with no statistically significant differences. Bland–Altman analysis confirmed good agreement in the precision of vestibulolingual linear measurements between CBCT and STL models when referenced to plaster models.

Conclusion: The study demonstrated good agreement in vestibulolingual linear measurements between CBCT and STL models when referenced to plaster models. However, mesiodistal linear measurements differed statistically among the different models. The observed differences highlight the value of combining these techniques alongside the continued development of digital tools