Pharyngeal airway volume and its relationship to the facial morphology in nasal breathing and mouth breathing subjects (A comparative computerized tomography study)

Abstract

Background: The value of lateral cephalometric radiographs to evaluate the pharyngeal airway is limited because itprovided 2-dimensional (2D) images of complex 3-dimensional (3D) anatomic structures. Three dimensional analysesof the airway volumes are required to understand oral and pharyngeal adaptations in mouth breathing and nasalbreathing subjects. The aim of this study was to measure the pharyngeal airway volume and the size of the face,then compare between pharyngeal airway volume in mouth breathing and nasal breathing subjects and find thegender difference in each group, also to study the relation between pharyngeal airway volume and the size of theface.Material and Methods: Fifty patients including 28 males and 22 females with an age ranged between 18-35 yearssuffered from clinical symptoms of nasal obstruction and mouth breathing was detected by otolaryngologist andsent to be imaged by Brilliance™ 64, Philips multi-detector computed tomography. Twenty normal subjects (10 malesand 10 females) were selected as control. Angular and linear variables were measured in addition to the size of theface and the pharyngeal airway volume.Results: A statistically significant relationship between the pharyngeal airway volume and the mode of respirationand between pharyngeal airway volume and genders were detected. The pharyngeal airway volume was larger innasal breathers than in mouth breathers and it was larger in males than in females. The size of the face was larger inmales than females.Conclusion: CT volumetric images provide more reliable and accurate information for measurement of thepharyngeal airway volume, so the changes in the pharyngeal airway volume can be studied before and aftersurgery and this will aid in selection of the best treatment option in addition to control the relapse after orthodontictreatment with mouth breathing patients