Objective: When the patient is pre-adolescent, functional appliances can influence dentofacial growth and ant-post posture of jaws but there would be some changes on other dimensions of face. The aim of this study was to demonstrate the influence of functional appliance on vertical and rotational growth of jaws.
Methods: As a clinical trial study, nineteen female Cl II div1 patients underwent functional therapy with functional for 12-18 months. Lateral cephalograms before and after treatment was compared with untreated control subjects .T-test was used for statistical analysis.
Results: Results Showed in vertical dimension increased specially in lower part of the face (p < 0.01). No significant changes occurred on rotational status of jaws (mandible P=0.86 and maxilla P=0.58) .There was a direct relation between increasing vertical dimension at posterior part of the face and forward rotation of mandible (P = 0.004) and dentoalveolar drift of mandible with its backward rotation (P=0.034).
Conclusions: As this appliance makes an increase in vertical dimension of face without significant rotation , it is preferred for normal and short face Cl II patients.