A sleep test was performed 108 times on 85 patients at the Self-Defense Forces Central Hospital for one year between September 1997 and August 1998. 36 patients (42%) had sleep apnea and 46 (57%) had simple snoring. Surgery was performed on 41 patients (55%) and a dental splint was used on 3 (4%). We issued a questionnaire about the effect of the therapy to the 44 patients after surgery and dental splint use. We received questionnaires back from 34 patients (77%). The improvement ratio of snoring was 94% and that of apnea during sleep was 93% after surgery. 88% of the patients raised their health awareness and 82% and significantly decreased their body weight after therapy.