Changes in the upper airway after counterclockwise maxillomandibular advancement in young Korean women with class II malocclusion deformity.

PURPOSE

To evaluate the change in the upper airway in a Class II malocclusion deformity after counterclockwise maxillomandibular advancement.

MATERIALS AND METHODS

Seventeen young Korean women with a Class II malocclusion deformity who had undergone Le Fort I and bilateral mandibular ramus sagittal split osteotomy in a counterclockwise rotation were enrolled in the present study. The upper airway was measured at 3 different levels (uvula tip, low C2, and mid C3) using lateral cephalograms at 3 points: preoperatively (T0) and 2 (T2) and 12 (T12) months postoperatively. The changes in the upper airway were then compared.

RESULTS

The mandible advanced an average of 7.0 ± 3.8 mm. The upper airway had widened considerably at all 3 levels at T2 and had decreased slightly at T12, especially at the low C2 level compared with T0. However, the upper airway at T12 remained wider than at T0 at all 3 levels. The mandibular advancement and upper airway width correlated only at T12 at the mid C3 level.

CONCLUSIONS

The upper airway became wider in patients with a Class II malocclusion deformity who had undergone mandibular advancement. However, this might become narrower with time.