Craniofacial morphology in patients with obstructive sleep apnea: cephalometric evaluation

Introduction: Obstructive sleep apnea is characterized by a reduced airflow through the upper airways during sleep. Two forms of obstructive sleep apnea are described: the central form and the obstructive form. The obstructive form is related to many factors, such as the craniofacial morphology. Objective: To evaluate the correlation between the morphology of the cranial base, of the mandible and the maxilla, and obstructive sleep apnea severity. Methods: Eighty-four patients, mean age of 50.4 years old; 73 males and 11 females with obstructive sleep apnea were enrolled in the present study. Patients with high body mass index and comorbidities were excluded. Lateral cephalograms and polysomnography were collected for each patient to evaluate the correlation between craniofacial morphology and obstructive sleep apnea severity. A Spearman's rho correlation test between cephalometric measurements and obstructive sleep apnea indexes was computed. Statistical significance was set at p < 0.05. Results: Patients with a severe obstructive sleep apnea presented a reduction of sagittal growth of both effective mandibular length and cranio-basal length. The mandibular length was the only variable with a statistical correlation with apnea-hypopnea index. Vertical dimension showed a weak correlation with the severity of obstructive sleep apnea. No correlation with maxillary sagittal dimension was shown. Conclusion: Obstructive sleep apnea severity may be correlated to mandibular and cranial base growth. Facial vertical dimension had no correlation with obstructive sleep apnea severity.