Objective: • Evaluate the impact of orthognathic surgery (bimaxillary or monomaxillary) and its movements on the PAV and the clinical indicators of OSA. Specific objectives: • Interrelate the degree of dentofacial deformity with the IAH. * Study the potential correlation between the volume of the VAS and the IAH. * Correlate the type, direction and magnitude of the surgical movements of the maxillofacial complex with PAV/PAS increase Correlate the type, direction and magnitude of the surgical movements of the maxillofacial complex with the cure of OSA (household PSG AHI assessment) and the following clinical indicators of OSA: diurnal hypersomnia test (ESD, ESS). * Evaluate negative effects of either maxillary or mandibular surgical movements in PAS/PAV increase and the cures of OSA. Evaluate negative effects of either maxillary or mandibular surgical movements in the improvement of the clinical symptoms and the cure of OSA. * To study the possible effect of surgical complications on PAS/PAV stability at long term and the clinical symptoms of OSA. * Demonstrate that maxillomandibular surgery is a defined, predictable and a definitive cure for OSA. * Demonstrate that skeletal, linear, and cross-sectional volume parameters remain stable at long-term. * Demonstrate that AHI and OSA-related parameters stay stable at long term after mono- or bimaxillary surgery. Hypothesis * H1a: Maxillomandibular advancement (orthognathic surgery) does correlate with the volume of the upper airway, at both short or long term. * H2a: Maxillomandibular advancement (orthognathic surgery) does correlate with the clinical indicators of obstructive sleep apnea, at both short or long term.