So far, the CPAP-therapy has established itself as the most effective treatement in patients with obstructive sleep apnea syndrome. In addition, there are several surgical alternatives for CPAP-therapy. But there are many patients who are either not open to or ineligible for those kinds of treatments. In contrast, this thesis focuses on the non-surgical
alternatives for the treatement of the obstructive sleep apnea syndrome. Studies show, that mandibular advancement devices, tongue-retaining-devices, the Velumount ® device, and positional trainers are possible alternatives for patients with mild to moderate obstructive sleep apnea syndrome. Nasopharyngeal stents and drug therapy seem to be less efficient.