Maxillary anterior teeth width and facial measurements among 21-28-year-old youths

Methods: A cross-sectional study was conducted on 100 dental students (21 to 28 years of age) in year 2011. In phase 1, the subjects were taken the frontal digital photographs of their face by a standardized method and the impression of their maxillary jaw by using alginate (Aroma, GC). In phase 2, it was taken the digital images of occlusal surfaces from their stone casts of  maxillary impressions. In final one, the photographs of their face and their maxillary cast were transferred into computer, then the AutoCAD software was applied to measure follwing dimensions: intercanthal distance, interpupillary distance, interalar width, intercommissural distance and width of 6 anterior teeth (circumferential/linear: canine tip to canine tip and distal canine surface to distal canine surface distance). The Pearson r Correlation  and biometric ratio were applied.

Results: Mean of values for extraoral and intraoral landmarks were: Intercanthal distance = 35.28±2.28 mm, interpupillary distance = 63.21±3.06 mm, interalar distance = 40.25±2.54 mm, intercommissural distance = 49.34± 3.54 mm. The intraoral ones were: circumferential/linear canine tip to canine tip distance= 41.67± 1.89 mm/ 35.49± 1.52 mm and circumferential/linear distal canine surface to distal cannine surfaces= 50.19±2.26 mm /38.40 ±1.59 mm. There were positive correlations existed between width of the maxillary anterior teeth and extraoral measurements (r = 0.226 à0.463, p<0.05) excepting the intercanthal distance in both male and female. A highest correlation was found between the interalar distance with the maxillary anterior teeth width on the cast, giving a biometric ratio of 1:1.25. 

Conclusions: The results suggested that the interalar width could be used as a preliminary method for estimating the maxillary anterior teeth width on daily clinical practices.