[Is hyperdivergence a contraindication in the early treatment of Class II malocclusion?].

Vertical growth pattern is supposed to have adverse effects on sagittal growth and is considered as a contra-indication for early treatment. The aim of this retrospective cohort study was to analyse whether early treatment of children with Class II malocclusion was able to achieve as an important sagittal correction on subjects with growth vertical pattern as on subjects without vertical pattern without modification of vertical growth. The study was composed of 123 children (110 months old in average), with Class II division 1 malocclusion : 34 children with excessive vertical growth pattern and 74 children without excessive vertical growth pattern, both treated with DAC appliance, and 15 not treated subjects with excessive vertical growth pattern. Data were collected at the start of the study (t(1)), after the active treatment (t(1')) and 29 months after t(1) (t(2)). A Pancherz cephalometric analysis was applied on the lateral roentgenograms. Differences were evaluated with t-test. Results show that DAC appliance may be an orthopedic appliance indicated to achieve correction in class II skeletal pattern by mandibular growth without augmentation of vertical dimension.