Efficacy of Oral Appliance for Mild, Moderate, and Severe Obstructive Sleep Apnea: A Meta‐analysis

Oral appliances (OA) are the recommended first-line option for mild-to-moderate obstructive sleep apnea (OSA)-hypopnea. However, there is a lack of evidence to compare the effectiveness of OA in different severities of OSA. The purpose of this study was to investigate the therapeutic effects of preferred OA (tongue retention devices [TRD] and mandibular advancement device [MAD]) in different severities of OSA.