Background and objectives: The purpose of this study was to retrospectively evaluate pharyngeal airway space (PAS) changes in patients who received mono or bimaxillary surgeries.

Methods: A cephalometric evaluation of 30 normal Chilean patients, after an orthognathic surgery. Only patients with pre and post operatory profile teleradiography were selected for this study. The radiographies were standardized in postural head position, without olives and in first teeth contact. Pre and post images had to be at the same scale (1:1). The patients were divided into 2 groups: group 1 underwent monomaxillary (Le Fort) advance surgery (9 patients); group 2 underwent bimaxillary advance surgery (21 patients). The PAS was evaluated with a handcraft cephalometric analysis of one operator, between one week postoperatively and six months postoperatively.

Results: Both type of surgeries, changed the PAS in the postoperative period. Monomaxillary advancement surgery achieved an expansion in the anterior posterior dimension at oropharynx level. After bimaxillary surgeries, there was an increase of the wide at nasopharynx. The Le Fort technique had the best performance, increasing de anterior posterior pharyngeal dimension at all levels (posterior nasal spine = 5.66 mm; soft palate = 2 mm; tongue = 2.33 mm; hyod = 1.167 mm). Bimaxillary surgeries had similar results, but at hyod level occurred a reduction of the airway (hyod = −0.417 mm).

Conclusion: The goal of this study was to understand and to predict the airway changes. All of this analysis is to propose a novel method for planning surgeries in patients with some disease like sleep apnea. Le Fort and bimaxillary techniques can be a real benefit to improve this type of alterations and also to prevent de occurrence of obstructive sleep apnea hypopnea syndrome (OSAHS).

Key words: pharyngeal; width; maxillary; OSAHS