<abstract xmlns="http://www.w3.org/1999/xhtml"><sec><h3>Introduction</h3><p>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.</p></sec><sec><h3>Methods</h3><p>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).</p></sec><sec><h3>Results</h3><p>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° (<italic>p</italic> = 0.004), ANB of 2.71° ± 1.01° (<italic>p</italic> = 0.00), Wits of 4.49 ± 2.21 mm (<italic>p</italic> = 0.00) and overjet of 4.90 ± 1.66 mm (<italic>p</italic> = 0.00) were accomplished and maintained without significant changes in the vertical dimension. Upper and lower incisor inclinations were not affected by the protraction protocol but significantly increased (U1-PP: 8.39° ± 5.59°) between T2 and T3. SNB decreased initially by 1.67° ± 1.34° (<italic>p</italic> = 0.00) but relapsed due to residual mandibular growth and a counterclockwise rotation of the mandibular plane.</p></sec><sec><h3>Conclusion</h3><p>The hybrid-Hyrax Alt-RAMEC combined with miniscrew reinforced heavy Class III elastics resulted in a favourable and stable Class III correction.</p></sec></abstract>

IntroductionThe 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.MethodsFifteen 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).ResultsA 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° (p = 0.004), ANB of 2.71° ± 1.01° (p = 0.00), Wits of 4.49 ± 2.21 mm (p = 0.00) and overjet of 4.90 ± 1.66 mm (p = 0.00) were accomplished and maintained without significant changes in the vertical dimension. Upper and lower incisor inclinations were not affected by the protraction protocol but significantly increased (U1-PP: 8.39° ± 5.59°) between T2 and T3. SNB decreased initially by 1.67° ± 1.34° (p = 0.00) but relapsed due to residual mandibular growth and a counterclockwise rotation of the mandibular plane.ConclusionThe hybrid-Hyrax Alt-RAMEC combined with miniscrew reinforced heavy Class III elastics resulted in a favourable and stable Class III correction.

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

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

IntroductionThe aim of this study was to evaluate the short- and long-term effects of hybrid-Hyrax, Alt-RAMEC and applied, miniscrew reinforced, heavy...

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

Published Online: Jul 30, 2021

Page range: 199 - 211

Received: Dec 01, 2016

Accepted: Jul 01, 2017

DOI: https://doi.org/10.21307/aoj-2020-099

© 2017 Alexandra K. Papadopoulou et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.