Oral appliances are indicated for the treatment of mild to moderate obstructive sleep apnea (OSA), yet insurance infrequently covers the costs associated with this therapy. Physicians remain hesitant to prescribe oral appliances for long-term use, particularly in younger patients with mild sleep-disordered breathing. These behaviors are the result, in part, of the paucity of long-term follow-up data on oral appliances. Research on the determination of long-term efficacy and compliance has relied too heavily on subjective measures (eg, patient/bed-partner satisfaction and self-report questionnaires) rather than more objective parameters such as treatment apnea-hypopnea index (AHI) and a continuous positive airway pressure (CPAP) data card equivalent. There is a need to evaluate systematically the efficacy of oral appliances using follow-up polysomnograms and to develop more objective measures of real-time compliance and efficacy.