Comparison of face mask treatment effects combined with different 'Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC)' protocols

Objective: The aim of this study is to investigate the skeletal, dental and soft tissue effects of face mask treatment combined with different Alt-RAMEC protocols in the Skeletal Class III patients with retrognathic maxilla in the pubertal period. Method: Forty patients who applied to Akdeniz University Faculty of Dentistry Department of Orthodontics were randomly assigned into two groups. Twenty patients in the first group were treated using the Alt-RAMEC of 9 weeks and second group were treated using 5 weeks protocol. At the end of the Alt-RAMEC protocol, expansion were continued, if needed. In both groups, a maxillary protraction force of 500 g per side with an anteroinferior force vector of approximately 30° to the occlusal plane were applied at the end of the Alt-RAMEC protocol. The patients were instructed to wear appliances for at least 20 hours per day until at least 2 mm of positive overjet were achieved. Pre and post-protraction cephalograms were evaluated by same researcher. Results: The groups were well matched in relation to gender distribution, chronological ages and initial cephalometric values of the patients. Both groups showed almost similar effects with no statistically significant differences. The maxillae moved forward and the mandible moved slightly downward and those changes caused an improvement in the maxilla-mandibular relationships in both groups. The overjet was increased and the overbite was decreased in both groups. Regarding to the soft tissue changes, the upper lip moved forward in both groups. Conclusion: The effects on the skeletal, dental and soft tissues of the 5-weeks and 9-weeks Alt-RAMEC protocols are similar. Key words: Alt-RAMEC, maxillary protraction, face mask