Cephalometric Comparison of a Modified Bionator (Farmand Appliance) and Twin-Block Appliance in Treatment of Skeletal Cl II Malocclusion

functional appliances with various designs have been introduced in the treatment of Class II malocclusions. The aim of this study was to evaluate dentoskeletal effects of a modified bionator (FA) and Twin Block (TB) functional appliance in treatment of skeletal Class II malocclusion.Method and material: in this retrospective study 30 treated cl II patients with overjet greater than 4 mm have been selected from each of two private offices. in each office either FA or TB were used. Pre-treatment and post-treatment lateral cephalograms were digitized and traced with Dolphin Imaging software. ANCOVA and paired T test were used for analysis with SPSS software (19). FA group consisted of 17 girls and 13 boys(mean age: 9.53± 1.1),TB group consisted of 12 boys and 18 girls(mean age: 10.26 ±.944). ANB angle and overjet were reduced significantly in both groups.(p=.000) Mandibular body length demonstrated a significant increase in both groups.(3.06±4.98mm with TB and 3.03±5.52mm with FA).In Both appliances significant retrusion of upper lip occurred as a result of decrease in overjet (TB=002,FA=.000).No statistical significant difference were found between two appliances. Treatment with both appliances resulted in correction of Class II discrepancy, reduction of overjet, and retrusion of upper lip. No significant dento-skeletal differences were observed between the 2 appliances