COMPARAÇÃO DA PREVALÊNCIA DA DISCREPÂNCIA DE BOLTON ENTRE AS MÁS OCLUSÕES DE ANGLE

Abstract

This study aimed to compare the overall and anterior proportion of tooth size discrepancies between Angle malocclusions. The following null hypothesis (H0) was tested: there is no difference between the tooth size discrepancies (overall and anterior) between Angle malocclusions. The sample consisted of 711 pre-orthodontic treatment study models of Brazilian patients, selected in private clinics in the city of Dourados / MS, with a mean age of 17 years. The specimens were divided into 4 groups according to the type of this malocclusion: Class I, 321 patients; Class II division 1, 306 patients; Class II, Division 2, 18 patients; and Class III, 66 patients. The dental measurements were obtained by using a digital caliper with centesimal precision directly on plaster models, including left first molar distal to right first molar distal. The ratio between the upper and lower teeth was measured by the method proposed by Bolton. The prevalence of tooth size discrepancy was measured in relation to sex and malocclusion. Chi-square, independent “t”, dependent “t”, Dahlberg’s formula and ANOVA to a criteria were applied, using SPSS 7.0 for Windows. The significance level was 5%, or P<0,05. The null hypothesis was accepted, since the results showed no difference in the overall and anterior proportion of tooth size discrepancies among the groups of Angle malocclusion.