Comparative Study of the Nasopharyngeal Airway Dimensions in Class II Individuals using Cone-beam Computed Tomography

Abstract

Objectives: The aims of our study were to use cone-beam computed tomography (CBCT) to assess the dimensional changes in the nasopharyngeal soft-tissue characteristics in Indian patients with Class II malocclusion and to compare the results with patients with ideal occlusion. Materials and methods: A sample of 20 patients (10 girls, 10 boys) with Class II malocclusion due to true mandibular retrognathism was selected. None of the subjects had a history of upper airway disease, adenoidectomy, or pathology in the pharynx. Cone-beam computed tomography scans were taken to measure the nasopharyngeal airway changes in terms of linear measurements, and sagittal cross-sectional areas. Error analysis was performed to prevent systematic or random errors. Independent mean t-tests and Pearson correlation analysis were used to evaluate sex differences and the correlations among the variables. Results: Nasopharyngeal soft-tissue characteristics in Class II subjects were different in male and female subjects. Men with Class II malocclusion have larger adenoid width areas than do women. Men also had greater sagittal thickness of the lower airway. The retroglossal and the total airway area were significantly greater in the control group. Conclusion: This study suggests new lines of investigation about the relationship between skeletal and dental anomalies and airway obstruction, and possible specific respiratory characteristics for each type of malocclusion.