Three-dimensional cone-beam computed tomography for assessment of airway changes with mandibular advance splint

Abstract

Upper airway constriction is an important contributing factor to obstructive sleep apnea (OSA), which may be treated in a palliative manner with mandibular advancement devices (MADs) to increase patency of the airway. It may be the treatment of choice for affected individuals who cannot use a continuous positive airway pressure device or who are not candidates for surgical correction of OSA. The specific distance applied during mandibular advancement, however, is often arbitrarily determined. This project uses cone beam computed tomography imaging in patients with OSA to determine a quantifiable relationship between airway patency and mandibular advancement. This correlation may be the basis to create an ideal technique to diagnose and treat patients having OSA. Twenty-six subjects successfully treated for OSA with a MAD received 2 cone beam computed tomography scans; 1 with and 1 without the MAD. Volumetric, cross-sectional, and cephalometric measurements were gathered from these scans. With the use of linear regression statistical analysis, specific predictor parameters have been identified for volumetric and cross- sectional airway information. An average oropharyngeal volume increase of approximately 2800 mm 3 was achieved with MAD therapy. Lateral airway dimensions of the cross- section at C2, total volume, and cross- sectional area gained in the oropharynx can be predicted from the amount of mandibular forward movement. Instituto de Investigaciones del Sueño for support.