This study is being done to see if treatment of obstructive sleep apnea (OSA) with a mandibular advancement device (MAD) shows an increase in the quality of life. Many patients prefer to call them mandibular advancers, jaw advancers, jaw advancement splints, jaw advancement devices, anti-snoring mouthpieces, or oral appliances for the treatment of snoring and mild to moderate obstructive sleep apnea. The investigators will also see how helpful the mandibular advancement device is on insulin resistance.

Patients with obstructive sleep apnea (OSA) will be included in this prospective controlled trial. OSA patients who are unable to tolerate CPAP or refuse CPAP(Continuous positive airway pressure) (and who are deemed appropriate by their attending physician for dental device treatment of OSA will be randomized to a control group (no MAD treatment) or to active MAD therapy.

Epidemiologic studies suggest that OSA is associated with insulin resistance independent of other known risk factors such as obesity. The cyclic intermittent hypoxia in OSA is the primary stimulus that leads to insulin resistance, a primary risk factor for the development of type 2 diabetes. There is an association between the level of hypoxic stress in OSA and insulin resistance.

The overall hypothesis to be tested is that treatment of OSA with MAD will improve insulin sensitivity, increase levels of HMW (High-molecular- weight) adiponectin, and improve psychological adjustment.

Inclusion Criteria:

• Apnea-hypopnea index (AHI) of at least 20 events/hr based on overnight polysomnography
• > 18 years of age
• Unable to tolerate or refuse CPAP treatment

Exclusion Criteria:

• Known diabetes mellitus

• Body mass index (BMI) > 45 kg/m2

• Uncontrolled hypertension

• Known congestive heart failure

• Use of illicit drugs

• Excessive alcohol consumption, defined as:

  • More than 3 glasses of wine a day
  • More than 3 beers a day
  • More than 60 mL of hard liquor a day

• Room air oxyhemoglobin saturation < 90%

• Use of home oxygen

• Use of corticosteroids

• Unable to give voluntary consent