Comparison of the Effect on SNA, SNB and ANB Angles Regarding Twin Block and Monoblock Activators Used in Class II, Division 1 Anomalies

Class II malocclusions are the most frequently encountered, therefore the most widely treated anomaly by orthodontists. In the treatment of this disorder where aesthetics, phonation and function are lost, orthodontics play a major role. Functional devices are widely utilized in the treatment of Class II anomalies. These devices are the ones which direct the force of a special muscle group with the aid of the dentition to the basal bone system by changing the function and position of the mandibula. In this study, the effect of two different activators used in the treatment of Class II Division 1 anomalies on the sagittal development of maxilla and mandibula were compared. The study was carried out on; group 1 consisting of 21 patients (11 girls, 10 boys) with an average of 13 treated with twin block, group 2 consisting of 17 patients (10 girls, 7 boys) with an average age of 12 treated with monoblock, group 3 consisting of 16 patients (9 girls, 7 boys) with an average age of 12 treated with monoblock- Headgear combination, group 4 consisting of 19 nontreated patients (11 girls, 8 boys) with an average age of 12. In order to test the similarity of the values at the treatment/control beginning and end within the groups, Variance analysis and Duncan test were applied to the initial and final cephalometric values. As a result it was seen that the design of the activator can have an effect on the inhibition of the maxillary development. However, the provocation of the mandibulary development is not inspired by the activator design but by the amount of the activation and the daily use of the device.