[Evaluation of upper airway dimension among adolescent patients with different sagittal skeletal patterns by cone-beam CT].

Purpose: To analyze whether upper airway dimensions were influenced by different sagittal skeletal pattern among adolescent patients.

Methods: Seventy-five adolescent patients were divided into 3 groups based on their ANB angles．The three groups were matched for age and sex． All subjects had a normodivergent skeletal pattern．Airway lengths, cross-sectional measurements and volumes were measured by using cone-beam computed tomography (CBCT) volume scans, and two-dimensional lateral cephalograms were created and analyzed. Airway lengths, cross-sectional measurements and volumes were compared among 3 groups. Statistical analysis was performed using SPSS 22.0 software package.

Results: No significant difference among the three groups was found in Anp, Lnp, Lvp, Lgp and Lhp cross-sectional areas of the airway. The glossopharynx volume was smaller in Class II[(2.34±0.79)mL] than in Class Ⅲ[(3.18±0.63)mL] patients(P<0.05). Total upper airway volume in Class II[(13.89±2.51)mL] patients was smaller than in Class Ⅰ[(16.48±4.41)mL] and Ⅲ[(17.47±3.55)mL] patients(P<0.05).

Conclusions: Upper airway volume is significantly reduced in Class II sagittal skeletal pattern, leading to a higher risk of obstructive sleep apnea/hypopnea syndrome.