Pharyngeal airway changes associated with maxillary distraction osteogenesis in adult cleft lip and palate patients

To investigate 1) the changes in pharyngeal airway sizes associated with maxillary distraction osteogenesis and 2) the correlations between maxillary skeletal variables and the pharyngeal airway in adult patients with cleft lip and palate.

The study was carried out in 14 adult subjects with cleft lip and palate. Predistraction records were taken at a mean age of 22.7 ± 4.6 years. All patients had placement of a rigid external distraction device (RED I; KLS Martin, Tuttlingen, Germany) after Le Fort I osteotomy. Lateral cephalograms were assessed before surgery and at short-term follow-up (8.0 ± 6.4 months). The cephalometric skeletal and pharyngeal airway variables were statistically evaluated by use of the Wilcoxon signed-rank test. Spearman ρ correlation was performed to check the correlations between maxillary skeletal and pharyngeal variables.

The maxillary movement was 8.7 mm (P < .01). The maxillary depth angle (+7.9°) and effective maxillary length (9.4 mm) increased significantly (P < .01) after distraction, whereas the palatal plane angle remained unchanged. Anterior nasal spine (8.2 mm) and Posterior nasal spine (6.9 mm) moved anteriorly. The overjet increased (9.5 mm) significantly (P < .01). Posterior, superoposterior, and middle airway spaces increased significantly, with mean differences of 7.5 mm, 5.1 mm, and 3.3 mm, respectively. The soft palate moved anteriorly, with the greatest movement at its superior point. Significant positive correlations were observed for the posterior and superoposterior airway spaces and maxillary movement. PNS changes showed the highest correlation with posterior airway changes.

The significant anterior movement of the maxilla resulted in significant increases in posterior, superoposterior, and middle airway spaces. The posterior airway space showed the highest significant positive correlation with the movement of PNS. The posterior and superoposterior airway spaces also showed significant positive correlations with the maxillary skeletal variables.