Early Orthopedic Correction of Skeletal Class ll Division 1 by Modified Bionator

Objective: The purpose of this study was to evaluate the early treatment effects of the modified bionator with J-hook on soft tissue of growing patients with skeletal Class II division 1 malocclusion. Materials and Methods: This investigation was conducted on 12 patients. All the patients had the following criteria: skeletal Class II division 1 due to mandibular retrusion with maxillary excess. Age ranged from 8-12 (mixed dentition and early permanent dentition). ANB° was more than 6°. Overjet was more than 5 mm. Lateral cephalometric radiographs, photographs and study casts were obtained before and after treatment. The collected data were analyzed using SPSS Version 22.0. The treatment continued for almost 17 months. Results: The appliance had dento-skeletal and soft tissue effects, which were established by the following significant changes: improvement of the maxillo-mandibular relationship, slight increase in the anterior facial height, decreased the overjet, stimulation of the forward growth of the mandible, restriction of the forward and downward growth of the maxilla and improvement in the soft tissue profile. Conclusion: The modified bionator with J-hook was effective in the treatment of growing patients with class II division 1 malocclusion. The appliance had skeletal effects in the sagittal plane by restricting maxillary growth and stimulating the forward growth of the mandible. The overjet was reduced due to the increased forward growth of the mandible and palatal tipping of upper incisors. The appliance improved the vertical dimension of the face and the facial profile.