RPE COMBINED WITH FACE MASK VERSUS DOUBLE HINGED EXPANDER COMBINED WITH ALT-RAMEC?

AIMS: Skeletal Class III malocclusions are characterized by maxillary retrognathia, mandibular prognathia, or a combination of both. Growth modification methods are applied for the treatment of skeletal anomalies in the early growth period. Class III anomalies with maxillary retrognathia in the early stages of skeletal growth are usually treated with a combination of maxillary expansion and face mask (FM). However, in recent years, alternate rapid maxillary expansions-constrictions (Alt-RAMEC) method has been applied in sagittal and transverse maxillary deficiencies. The null hypothesis of this study is that the application of double-hinged expander (DHE) combined with Alt-RAMEC during the appropriate skeletal growth period produces skeletal result similar to a FM effect. To test this hypothesis, the study aims to evaluate the position of the maxilla in three dimensions immediately after the application of the DHE combined with Alt-RAMEC protocol in Class III malocclusion associated with maxillary retrusion.

MATERIAL AND METHODS: A total of 18 individuals, 11 girls and 7 boys (mean chronological age 14.00 years and 13,85 years) with Class III malocclusion associated with maxillary retrusion, who presented to the Department of Orthodontics, Faculty of Dentistry, Ankara University, were treated with Alt-RAMEC and DHE. The DHE was opened four times a day, twice in the morn- ing and twice in the evening in the first week for a daily activation of 1 mm; in the second week, it was closed with the same frequency; the repeated series was termi- nated with expansion at week 9th. The maxilla was evaluated sagitally, vertically and transversally on lateral cephalometric and posteroanterior radiographs at the beginning (T1) and 9th week (T2) of the treatment.

RESULTS: It was found that themaxilla advanced approximately 2.54 mm sagittally, expanded 1.01 mm in the premolar region and 0.89 mm in the molar region transversely, while the vertical movement wasn’t statistically significant.

CONCLUSIONS: The hypothesis proposed in this study has been proved to be correct. During the appropriate skeletal growth period, the combination of DHE and Alt-RAMEC protocol provides maxillary sagittal growth similar to the FM effect reported in the literature.