Comparison of the treatment effects of upper molar distalization with mini screw assisted pendulum appliance and infrazygomatic crest screws

Aim: To compare the dentofacial effects of distalization with mini screw supported pendulum (MVDP) and infrazygomatic crest (IZC) screws. Methods: The data of the retrospective study were taken from the archive of Adıyaman University Faculty of Dentistry, Department of Orthodontics. Individuals were divided into two groups according to molar distalization methods. The first group consisted of individuals who were treated with the MVDP appliance (14 girls, 5 boys, mean age: 16.9±1.46) and the second group (8 girls, 9 boys, mean age: 17±1.68) who were treated with an IZC screw. Dental, skeletal and soft tissue measurements were made on lateral cephalometric radiographs taken before (T0) and after (T1) distalization. Results: Statistically significant (p<0.001) molar distalizations were observed in the MVDP group, 3.52±0.76 mm at 8.71±2.02 months, and 3.5±0.74 mm at 9.7±2.5 months in the IZC group. The amount of distalization in the premolar teeth was significantly less (p<0.01) in the MVDP group (1.73±1.09 mm) than in the IZC group (2.81±0.79 mm). Significant (p<0.001) tipping was observed in molar teeth in both groups, but no significant difference was found between the groups (p>0.05). The retrusion and retroclination of incisors were significantly higher in the IZC (2.75 mm/9.87°) group than in the MVDP (0.98 mm/3.88°) group (p<0.01). A significant difference (p<0.001) was found between the groups in terms of the change in the amount of overjet. Conclusion: Both distalization methods are found to be effective in obtaining a class I molar relationship in individuals with class II malocclusion. Keywords: Molar distalization, Infrazygomatic crest screw, Mini screw supported pendulum