Short-term effects of a modified Alt-RAMEC protocol for early treatment of Class III malocclusion: a controlled study.

OBJECTIVES: To assess the effects of a modified alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol in combination with facemask (FM) in Class III growing patients.

SETTING AND SAMPLE POPULATION: Thirty one Class III patients (17 males, 14 females) were treated with a modified Alt-RAMEC/FM protocol at the Department of Orthodontics of the University of Florence.

MATERIAL AND METHODS: All patients were evaluated at the beginning (T1, mean age 6.4 ± 0.8 years) and at the end of orthopedic therapy (T2, mean age 8.1 ± 0.9 years), and they were compared to a matched sample of 31 Class III patients (16 males and 15 females) treated with rapid maxillary expansion and facemask (RME/FM) and to a matched control group of 21 subjects (9 males and 12 females) with untreated Class III malocclusion. The three groups were compared with anova with Benjamini-Hochberg correction for multiple tests.

RESULTS: Both the Alt-RAMEC/FM and the RME/FM protocols showed significantly favorable effects leading to correction of the Class III malocclusion. The Alt-RAMEC/FM protocol produced a more effective advancement of the maxilla (SNA +1.2°) and greater intermaxillary changes (ANB +1.7°) vs. the RME/FM protocol. No significant differences were recorded as for mandibular skeletal changes and vertical skeletal relationships.

CONCLUSION: The Alt-RAMEC/FM protocol induced more favorable skeletal short-term effects compared with RME/FM therapy in Class III growing patients.