Dento-skeletal effects of myofunctional appliance on patients with class II div 1 in mixed dentition stage: A cephalometric study

Abstract Background and aim Myofunctional appliances are commonly used to stimulating positively the masticatory and tongue muscle activity, altering the posture of the mandible to a more forward position. These appliances could be effective in treating the Class II, Division 1 in the mixed dentition stage. The purpose of the clinical study was to evaluate the effects of Multi-P as a prefabricated functional appliance on the dento-skeletal structure in patients with Class II, Division 1 in the mixed dentition stage. Material and methods This clinical study consisted of 18 pediatric patients (mean age 9.97 ± 1.36 years) with Class II Division 1 malocclusion. The Multi-P appliance was used in the treatment of all patients. Pre- and post-treatment cephalometric radiographs were evaluated to analyze the changes in dento-skeletal dimensions during the treatment period. Results When the pre-and post-treatment cephalometrics were compared, it was found that there were insignificant differences for the SNB°, SN-GoGn°, and Co-Gn distance (p ≥ 0.05). It was observed that the Go-Gn (p = 0.03) and SN (p = 0.033) distances remarkably increased, After the treatment, significant increases were observed in IMPA (p = 0.001) and ANB° (p = 0.001), and a significant decrease was found in U1-FH° (p = 0.023). Also, a significant reduction in the overjet was recorded in the patients (p = 0.000). The average treatment time was found to be 2.94 ± 0.70 years. Conclusion Based on our results, it can be concluded that the Multi-P prefabricated myofunctional appliance for Class II, Division 1 malocclusion has mostly dentoalveolar effects without significant skeletal effects in the mixed dentition stage.