Mestizo anterior teeth’s proportions

Teeth proportions relate to beauty and harmony but aesthetic dental ideal proportion models show inconsistent results. Golden Proportion´s, Preston’s, Fayyad’s, Snow’s, and Ward’s models where characterized for best fit in a Colombian mestizo population anterior teeth. Models of teeth´s beauty proportions (Golden Proportion´s, Preston’s, Fayyad’s, Snow’s, and Ward’) are analyzed for best fit in a mestizo (mixed race) Colombian population and variables as sex, aesthetic balance or history of previous orthodontic treatments were also analyzed for their probable impact on the distribution of the dental proportions. It was used standardized photographs of anterior teeth on 351 individuals of both sexes with complete erupted and healthy teeth. The measurements were done by calibrated computer software (error of 0.05 mm). A Chi squared test was used to check whether sex, aesthetic balance and previous orthodontic treatment had an impact on the distribution of the dental proportions. Also a nonparametric Wilcoxon test was used to analysis the null hypothesis. A cluster analysis using k means was carried out to search for subgroups, which better explain the distribution of anterior dental proportions in the sample. For the considered results the null hypothesis of the mean equaling to the Golden Proportion was rejected (Wilcoxon test p value <0.001). For the whole population, the Chi squared test did not reject the null hypothesis of equal proportions among the groups with respect to the sex (p value= 0.56), aesthetic balance (p value= 0.98) and history of previous orthodontic treatments (p value= 0.67) variables. For the aesthetically balanced individuals, the Chi squared test also failed to reject the null hypothesis of equal proportions among the groups with respect to the sex (p value= 0.63) and history of previous orthodontic treatments (p value= 0.93) variables. Two Gaussian distributions were found for RED models fitting well in 58% for RED 70% (0.7 SD 0.03) and 42% for RED 75 (0.75 SD 0.025). From the cluster analysis using k means, two groups were identified in the whole sample. No universal model can describe the whole population but is possible to find a set of models for the different population subgroups. Aesthetically ideals are open to interpretation. Clinical aesthetically standards for ideal teeth proportions are open to interpretation in a mestizo (mixed raced) population.