Computerized cephalometric study of the pharyngeal airway space in patients submitted to orthognathic surgery

Pharynx is a muscular organ with is sustained by craniofacial bones. It is divided into nasal, oral and hipopharynx, and can be considered as a tube that serves both respiratory and digestive systems. Its anatomical morphology permits that factors facilitate its obstruction, leading to the sleep apnea syndrome. One of the treatment consists of surgical mandibular advancement, increasing pharyngeal dimensions. The aim of this study was evaluate the cephalometric changes in the pharyngeal airway space after orthognathic surgery procedures for correction of mandibular prognathism.

Pre and post-operative cephalometric analysis was performed on 19 patients submitted to mandibular setback by mandibular bilateral sagittal split osteotomy associated with maxillary advancement by Le Fort I osteotomy, using the Dolphin Imaging 10.0 software.

Results did not reveal statistically significant changes in the upper (nasopharyngeal), middle (oropharyngeal) and lower (hypopharyngeal) airway spaces, but showed increase in the nasal pharynx due the maxillary advancement and a lower position of the hyoid bone due the mandibular setback.

Maxillomandibular orthognathic surgery for correction of mandibular prognathism does not seem to statistically significantly change the pharyngeal airway space, but it increases the maxillary airway.

It seems to be important to consider the double jaw surgery in cases of mandibular prognathism, aiming prevention of a possible reduction of whole upper airway.