The relation between overbite and facial, maxillary and mandibular dimensions

Background : Overbite value is important in treatment of various malocclusions ; the aim of this study was to investigate the relation between the overbite and facial, maxillary and mandible dimensions. Materials and methods : The sample of this study included 80 pre-treatment digital true lateral Cephalometric radiographs of Iraqi subjects aged 18-25 years, collected from the files of the subjects attending the Orthodontic Department in the College of Dentistry, University of Baghdad. The 80 radiographs were divided into four groups (20 Radiographs each) according to overbite value. Three angular, fifteen linear measurements and two ratios were used. Results : There were significant differences in most vertical linear measurements, while no significant differences in horizontal linear measurements between over bite groups also there were strong negative correlation between over bite and SN-MP, PP-MP, gonial angles. Conclusions : There were significant correlation between over bite and facial, maxillary and mandible dimensions. Patients in open bite group showed longer lower facial height, maxillary and mandible alveolar and basal heights, symphyseal height and tendency toward backward rotation of the mandible than other overbite groups patients.