Abstract: Methods: The obturators rehabilitating the upper airway was reconstructed based on the CT graphs of a patient after unilateral complete resection of maxilla and the airflow was numerically simulated using the method of CFD. Results After restoration with high open, high closed, medium open, medium closed, low open, low closed obturators respectively, the airflow trends in both inspiration and expiration phases were obtained; the comparison of velocity contours, vorticity contours and area for each cross-section between the healthy side and the affected side was made. Conclusions Rehabilitation of various obturators cannot change the flow pattern of airflow in the cavity, and closed type can fill the defected cavity, thus changing the length-depth ratio and the low-velocity vortex area. Medium closed type ones are recommended as they can reduce the vorticity area substantially during both the inspiration and expiration phases.

Key words: the upper airway, air movement, numerical simulation, obturator prosthesis