The effect of posterior bite plane on dento skeletal changes in skeletal open bite malocclusion

With regard to the vertical problem of skeletal open bite malocclusion and using posterior bite plane this study was undertaken to evaluate the effect of upper posterior bite plane on the dentoskeletal changes in patients with skeletal open bite The material consisted of 19 patients, with skeletal open bite in mixed dentition period. The patients were treated by upper removable posterior bite plane appliance. Lateral Cephalogrom before and after treatment was obtained and traced. Certain angular and linear variables were measured. The pre treatment and post treatment measurements were compared using Paired t-test to evaluate the significance of the results. . There were significant changes in vertical incisor overlap following treatment with upper posterior bite plane.. Increase of PFH, Jaraback index UAFH/LAFH ratio were significant. There was decrease of SN-MP angle The dentoalveolar heights of the upper and lower anterior segment were increased as well as the distance of the lower molars to vertical and sagital lines only the maxillary first molar height and its distance to the vertical reference line did not change. The use of upper removable posterior bite plane during mixed dentition period in skeletal open bite patients causes counter clockwise rotation of mandible and an increase in the posterior facial height.