Background: Class II malocclusion is one of the most common orthodontic problem.The main reason for seeking orthodontic treatment for Class II malocclusions is aesthetic improvement. In case of skeletal malocclusion, treatment options change according to patientís age. In younger patients with significant growth potential, best treatment result is usually achieved by growth modification by using myofunctional appliances. The present study was done to assess the skeletal changes using Twin block appliance. Material and methods: The study was conducted in the department of Orthodontics and dentofacial orthopaedics to assess the skeletal changes using Twin Block in 15 patients. Cephalometric radiographs of the patients were obtained at the beginning of the study (Ceph1) and at end of the treatment (Ceph 2). Standard twin block appliance was used to correct class II malocclusion with deficient mandible. Steinerís analysis and Wittís appraisal were used to assess the skeletal changes. Statistical analysis was performed using the Statistical Package for the Social Sciences software version 21.0 (SPSS Inc., Chicago, IL, USA). A p-value <0.05 was predetermined as statistically significant. Results: In the present study total sample size was 15 in which 53% were boys and 47% were girls. The study showed significant variations between pre treatment and post treatment findings.SNA value was found to be decreased which showed a restrictive effect of Twin block on maxilla. An increase in the SNB angle indicated a forward shift of mandible. The spatial position of the mandible related to the anterior cranial base (SND) was found to be increased whereas a significant reduction ( p<0.05) in the measurements related to maxillo mandibular sagittal position (ANB, AO-BO) was obtained. Conclusion: Result of the present study showed significant improvement in spatial position of mandible and in the relative sagittal position of maxilla and mandible.
Key words: Maxillomandibular, Sagittal, Twin block appliance.