Perception esthétique de la position verticale des bords libres des incisives latérales maxillaires dans l’arc du sourire

Abstract

The aim of this study is to assess the attractiveness in the smile arch of different vertical positions of the incisal edges of the maxillary lateral incisors. A frontal photograph of a Caucasian woman's smile was digitally modified to obtain an image with the incisal edges of the maxillary lateral incisors symmetrically tangent to the smile arch. These incisal edges were then moved vertically by 0.5 mm increments. The value was considered positive for an occlusal shift and negative for a gingival shift. Four other images were obtained by moving the incisal edges from +0.5 mm to -1.5 mm. The five images were rated on a visual analog scale by three groups of evaluators: orthodontists, dentists and laypersons. A statistical analysis was performed. Laypersons preferred first lateral incisors tangent to the smile arch, second a +0.5 mm shift, and third a -0.5 mm shift. Orthodontists and dentists preferred first a -0.5 mm shift and second a null shift. The aesthetic perception of the smile, as regard to the vertical relationships between the incisal edges of the anterior teeth, differs between laypersons and professionals but remains homogenous between orthodontists and dentists. The most consensual aesthetic situation, from both professionals' and laypersons' points of view, is the geometry in which the incisal edges of the maxillary lateral incisors are tangent to the smile arch.