Efficacy of gender on the width-length ratio of maxillary anterior teeth in an Egyptian population and establishment of a guideline for esthetical accepted ratio of teeth dimensions to gingival display

Aim: The present study aims to correlate between gender and width-length ratio of maxillary anterior teeth in a sample of Egyptian population and to obtain an optimal esthetical accepted ratio of teeth dimensions to gingival display. Materials and Method: Stone casts were poured from irreversible hydrocolloid impressions of 100 adult Egyptian participants. These casts were used to measure the maximum mesiodistal width, maximum crown length and the width/length ratio for each maxillary anterior tooth. In addition, two frontal photographs were taken for each participant and the visible anterior teeth width, length and width/length ratio were measured. Finally, a sample with gummy smile was selected and the gingival display of the original image was digitally manipulated to create a series of five images with different gingival displays, then these images were subjected to assessment by 50 dentists and 50 laypersons using a numerical rating scale. Results: There was statistically significant difference between female and male group for all teeth width values and W/L ratio of lateral incisor and canine. There was no significant difference between dentists and laypersons perception except for the smile with -4 mm gingival display. Conclusion: Gender affects actual teeth width values as well as actual and apparent W/L ratios of lateral incisor and canine. Laypersons considered 0mm and -2mm gingival display the most attractive situation, on the other hand dentists considered 0 mm gingival display the most attractive one, while all participants agreed that 4mm gingival display is the least attractive one.