Abstract
BACKGROUND: Intraoral scanners (IOS) are increasingly utilized in pediatric dentistry to capture digital impressions, offering advantages over traditional impression materials, particularly in young patients. However, the accuracy and precision of these devices may be influenced by factors such as limited mouth opening, which is common in pediatric patients. This study aims to evaluate the effect of mouth opening on the accuracy of intraoral digital impressions obtained via two different IOS technologies: confocal microscopy (Trios 5) and structured light triangulation (Helios 600). METHODS: A typodont deciduous teeth model was scanned at three mouth opening levels (28 mm, 33 mm, 37 mm) using both IOS. Accuracy was analyzed through two-dimensional (2D) linear measurements and three-dimensional (3D) superimpositions, assessing trueness and precision. Statistical analysis was performed using Kruskal–Wallis and Mann–Whitney U tests (p < 0.05). RESULTS: At all mouth opening levels, no statistically significant differences in trueness were observed between the two scanners (p > 0.05). However, a significant difference in precision was found at the 28 mm opening, where the Helios 600 exhibited notably lower 2D precision compared to the Trios 5, both in the maxilla (p = 0.02) and mandible (p = 0.03). The 3D precision values for scans obtained with the Helios 600 were statistically significantly lower than those obtained with the Trios 5, both in the maxilla (p = 0.017) and mandible (p = 0.021). No significant differences in precision were observed at the 33 mm and 37 mm openings (p > 0.05). CONCLUSIONS: This study demonstrated that both the Trios 5 and Helios 600 intraoral scanners provided clinically acceptable trueness values. However, Trios 5 exhibited significantly better precision, particularly in cases with limited mouth opening. These results suggest that Trios 5 may offer improved reliability, especially for pediatric patients with reduced mouth opening.