Digital Analysis of Occlusal Contacts in Angle Class II and Class III Malocclusion

To evaluate the number, interocclusal distance categories, and spatial distribution of occlusal contacts per subject in Angle Class II and Class III malocclusions using digital intraoral models.

This exploratory, cross-sectional study evaluated 60 untreated subjects (30 Class II, 30 Class III). Digital models were obtained via the Medit i600 intraoral scanner, and contact analysis was performed using the Medit Occlusion Analyzer software. Variables represented the cumulative number of teeth per subject. Data were analyzed using median and interquartile range (IQR). Intergroup comparisons were performed using Mann-Whitney U tests (α = 0.05), with effect size estimated using rank-biserial correlation (rB).

Premolar contacts showed no significant intergroup differences regarding interocclusal distance (p > 0.05). However, Class III subjects exhibited significantly more molar contacts within the 0.050-0.100 mm distance range (p = 0.018). Full-surface contacts were significantly more frequent in Class II patients for both premolars (p = 0.002) and molars (p = 0.007). Class II subjects also showed a highly significant complete absence of molar contacts (p < 0.001). Palatal distribution of premolar contacts showed a borderline difference (p = 0.044), interpreted as a clinical trend.

Digital analysis revealed specific patterns in the interocclusal distance and distribution of occlusal contacts in Angle Class II and Class III malocclusions. Intraoral scanning provided objective geometric data that can serve as a valuable adjunct for individualized treatment planning.