Airway changes in growing Class II patients treated with Herbst appliance: A randomized controlled trial (RCT) comparing dental and skeletal anchorage.

OBJECTIVE

To evaluate changes in the oropharyngeal airway (OP) with Herbst appliances using either dental or skeletal anchorage (HDA vs. HSA) in growing patients with Class II division 1 malocclusion.

DESIGN, SETTING, AND

PARTICIPANTS

Forty patients (12.6 ± 1.4 years) at the peak of pubertal growth were randomized (HDA= 20; HSA= 20), for 12 months. Outcomes: change in OP volume, airway length and cross-sectional areas (minimum, maximum, average), by CBCT.

RESULTS

Thirty-four patients completed the study (HDA= 19; HSA= 15); and intention-to-treat (ITT) analysis was applied. Within-group analysis revealed a significant improvement for minimum axial area (HDA, p = .0061). Between-group comparisons showed significantly higher mean values in the HSA group for volume (p = .0044), airway length (p = .004), maximum cross-sectional area (p = .0188), and average area (p = .0122).

CONCLUSIONS

HSA and HDA increased OP dimensions in growing Class II patients. Although HSA did not demonstrate a statistically superior effect, the dimensional changes represent morphological adaptations. Long-term studies are required to determine respiratory benefits.