Abstract

The aim of this study was to determine changes of tongue position and oropharyngeal space following treatment with functional appliance in patients with class II div I malocclusion. In this before-after clinical trial, 28 patients with class II div I malocclusion were investigated. The range of age of females was 10-13 years and males 11-14 years. These samples were treated for 11 months. McNamara analysis and some linear variables were used to determine positional changes of tongue and oropharyngeal space. In this study, tongue moved significantly (Rvalue < 0.05) forwards in the horizontal dimension and non - significantly downwards in the vertical dimension. Treatment with functional appliance leads to significant alterations in tongue position and significantly increases the extent of oropharyngeal space.