Esthetic perception of mandibular anterior teeth during speech and dynamic smile

This study evaluated the esthetic perception of the mandibular anterior teeth during speech by comparing the assessments of laypeople (LP) and orthodontists (ODs).

A Class I occlusion model was filmed pronouncing "Czechoslovakia" and smiling. Dynamic smile and speech images were extracted and digitally manipulated to create various dental conditions: ideal alignment, mandibular canine extrusion, mandibular incisor crowding, inclined mandibular occlusal plane, mandibular incisor diastema, and mandibular incisor extraction simulation. Forty-eight participants from each group (LP and ODs) evaluated images using visual analog scales. Statistical analysis employed repeated measures analysis of variance with a 5% significance level.

No significant differences appeared between evaluator group means except for the dynamic smile image. Dynamic smile images received the highest scores, followed by aligned and leveled teeth, both showing significant differences (P <0.05) from each other and the remaining images. Inclined occlusal plane and diastema images received the lowest scores. Group evaluations showed distinct patterns: ODs did not significantly differentiate between canine extrusion, crowding, inclined occlusal plane, and diastema images, whereas LP showed no significant differentiation between incisor extraction, canine extrusion, crowding, and diastema images.

Speech images received lower attractiveness ratings than ideal occlusion in both groups. No significant differences appeared between LP and OD evaluations except for the dynamic smile image assessment.