Correlation of Type of Malocclusions and Cephalometric Parameters with Smile Characteristics in Lateral and Oblique Views

This study evaluated correlations between Angle’s Class I and Class II malocclusions, lateral cephalometric parameters, and smile characteristics assessed through lateral and oblique smile views.

A sample of 20 patients (≥15 years, with no prior orthodontic treatment) were selected for this study. The selected individuals were grouped according to Angle’s classification of malocclusion. Pretreatment records were taken including lateral cephalogram and extra-oral smile photographs in lateral and oblique views. In the lateral cephalogram, skeletal, dental, and facial parameters and in lateral and oblique smile views, smile index, commissure angle, and incisal display angle were recorded. ANOVA and Pearson correlation test were used for data analysis. P-value<0.05 was considered as significant.

The results of this study showed no significant difference in cephalometric parameters except for UFH/LFH, which was higher in Angle’s Class II malocclusion. The smile index, commissure angle and incisal display angle differed significantly between the two malocclusions in both lateral and oblique smile views except for incisal display angle in the oblique view. 

The lateral and oblique smile index decreased from Class I to Class II. In contrast, the lateral and oblique smile commissure angle and lateral smile incisal display angle increased in Class II compared to Class I. No significant difference was found in skeletal and dental parameters between Angle’s Class I and Class II malocclusions except for UFH/LFH, which was higher for Angle’s Class II malocclusion.