Dentoskeletal morphology of adult Class II division 1 and 2 severe deep overbite malocclusions

Abstract

IntroductionMorphological differences between Class II division 1 (II/1) and 2 (II/2) severe deep overbite malocclusions have not yet been established. Therefore, the present study aimed to identify the morphological components related to overbite in adult patients with these malocclusions. MethodsDental casts and cephalograms of II/1 (Group 1) and II/2 (Group 2) patients both with deep overbite (>5mm) and subjects with Class I normal occlusion, (12 males, 20 females; aged 18–35 years in each group) were selected. The skeletal and dental components were compared between groups by ANOVA and post-hoc Bonferroni correction. The relationship between depth of overbite and morphological components was analyzed in Groups 1 and 2 by Pearson correlation and multiple regression analysis. The significance level was set at 0.05. ResultsIn Group 1, the distance from the mandibular plane to the edge of mandibular central incisor showed a significant positive correlation with depth of overbite, which was greater than the other groups. In Group 2, the anteroposterior distance from A point to the mesial contact point of maxillary first molar showed a moderately significant positive correlation with depth of overbite and the distance from the palatal plane to the cusp tip of maxillary first molar showed a strongly significant negative correlation with depth of overbite, which was significantly smaller than the other groups. ConclusionsMandibular central incisor extrusion and maxillary first molar infraocclusion showed significant correlation to severe deep overbite in adult Class II division 1 and 2 malocclusions, respectively.