Effects of hybrid-Hyrax, Alt-RAMEC and miniscrew reinforced heavy Class III elastics in growing maxillary retrusive patients. A four-year follow-up pilot study
Pubblicato online: 30 lug 2021
Pagine: 199 - 211
Ricevuto: 01 dic 2016
Accettato: 01 lug 2017
DOI: https://doi.org/10.21307/aoj-2020-099
Parole chiave
© 2017 Alexandra K. Papadopoulou et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
Introduction
The aim of this study was to evaluate the short- and long-term effects of hybrid-Hyrax, Alt-RAMEC and applied, miniscrew reinforced, heavy intermaxillary elastics on a modified lingual arch in growing skeletal Class III patients.
Methods
Fifteen subjects (seven male, eight female) were included, with an average age of 12.52 ± 0.94 years, of cervical vertebrae maturation (CVM) stage CS2-CS4 and skeletal Class III malocclusions due to a retrognathic maxilla. Nine weeks of Alt-RAMEC were followed by eight to nine weeks of maxillary protraction with heavy 400 gm Class III elastics worn 24 h/day. Treatment was finalised with orthodontic fixed appliances. Cone beam computed tomographic (CBCT) scans were taken initially (T1), at the end of maxillary protraction (T2) and four years after active orthopaedic treatment (T3). Cephalometric measurements were performed on reconstructed lateral cephalograms and the differences between time intervals were calculated using an analysis of variance (ANOVA).
Results
A positive overjet was achieved in all but one subject. From T1 to T2, A point advanced 3.12 ± 3.42 mm and from T2 to T3 advanced a further 2.21 ± 3.49 mm. Significant initial increases in SNA of 1.05° ± 1.10° (
Conclusion
The hybrid-Hyrax Alt-RAMEC combined with miniscrew reinforced heavy Class III elastics resulted in a favourable and stable Class III correction.