The objectives of this study is to compare short-term outcomes of CPAP and TRD in the treatment of obstructive sleep apnea. Study design is a randomized cross-over trial during 3-weeks period of each treatment in 36 patients. Primary outcomes are quality of life, degree of sleepiness, and severity of OSA determined by FOSQ ESS, and AHI or RDI, respectively.

The objectives of this study is to compare short-term outcomes of CPAP and TRD in the treatment of obstructive sleep apnea. Study design is a randomized cross-over trial during 3-weeks period of each treatment in 36 patients. Primary outcomes are quality of life, degree of sleepiness, and severity of OSA determined by FOSQ ESS, and AHI or RDI, respectively. Wash-in period 1 week and Wash-out periods 1 week are required before start each treatment.

Inclusion Criteria:

1. OSA patients aged over 18 years old at Siriraj hospital
2. Apnea-hypopnea index (AHI) 5 - 30 events/ h or AHI > 30 events/h but lowest Oxygen saturation > 70%
3. Positive consented form

Exclusion Criteria:

1. Patients with severe periodontal diseases
2. Patients with unstable medical problems i.e. poorly controlled cardiovascular diseases, cancers, cerebrovascular diseases, epilepsy, dementia, etc.
3. total sleep time less than 2 hour during previous sleep study
4. Patients who could not tolerate the side effects of CPAP or TRD
5. Patients who could not follow-up until finishing the protocol or withdraw themselves from the study for any reasons.