Efficacy of torus mandibularis resection in a patient with obstructive sleep apnea (OSA): A case report

Abstract Introduction The aim of this study was to assess the contribution of a large torus mandibularis to induction of obstructive sleep apnea (OSA) due to upper-airway obstruction and to examine the efficacy of torus mandibularis resection in expanding the upper airway. Methods The Japanese version of the Epworth Sleepiness Scale (JESS), unattended portable sleep monitoring and computed tomography (CT) were performed before and at 18 months after surgery. Result The JESS score changed from 6 to 4. The lowest SpO 2 and the percentage of time during which the SpO 2 was 3 to 6,166.58 mm 3 at the level of the posterior soft palate, and from 8,802.93 mm 3 to 12,444.68 mm 3 at the level of the posterior tongue. The volume enlargement ratio evident on 3D image reconstruction was 92.8% at the level of the posterior soft palate and 143.37% at the level of the posterior tongue. The distance from the apex linguae to the anterosuperior point of the hyoid changed from 60 mm to 65 mm, and the distance from the SN plane to the superior point of the dorsum linguae changed from 53 mm to 47 mm. Conclusion Resection of a large torus mandibularis results in expansion of the upper- airway and may reduce airway obstruction during sleep.