The purpose of this study was to evaluate the tooth size discrepancies in patients of Rio de Janeiro State University Orthodontic Clinic. The sample was composed of 161 patients, which fulfilled the including criteria. Mesiodistal width of all permanent teeth were measured, from first left molar to first right molar, in both arches. The Bolton's discrepancy ratio was calculated for each set of models. The means for overall and anterior ratios were obtained for the whole sample, also evaluating differences between sexes and malocclusion (Angle's Class I, Class II and Class III). The values found were compared to Bolton's means. The overall and anterior ratios demonstrated no significant differences between sexes. No significant differences were found among the means obtained for each malocclusion group. These results suggested no influence of malocclusion status in the intermaxillary tooth size ratios of the studied sample. However, when comparing the sample's means to the one proposed in Bolton's analysis, it was found that they were greater for the whole sample, for both sexes and for Class I and Class II patients, indicating the tooth size discrepancies could occur more frequently in malocclusion groups than in patients with normal occlusion. The overall and anterior ratio found for malocclusion group of Class III did not demonstrate significant differences when compared to Bolton's means.
Mesiodistal width; Bolton's Analysis; Tooth discrepancy
