A Comprehensive Classification of Snoring Appliances: A Systematic Review

Introduction: Obstructive sleep apnea (OSA) and snoring are common conditions that adversely affect sleep quality. Snoring has several etiologies; however, difficulty in airflow through the upper airways is considered a principal mechanism. If snoring persists despite addressing the underlying causes, appliances can help reduce snoring. A variety of appliances with different mechanisms have been proposed. This review aimed to classify appliances, their mechanisms of action, and methods of fabrication. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was performed in PubMed, Scopus, and Google Scholar for studies published between 1995 and 2024 using the following keywords: mandibular advancement devices, obstructive sleep apnea, snoring, continuous positive airway pressure, and dentistry. Results: Of the 200 initially identified articles, 25 relevant abstracts were selected for full- text review, and 13 studies were ultimately included in the review. This study investigated the fabrication methods and characteristics of snoring appliances. Based on the reviewed literature, appliances used for snoring and OSA management were categorized into five groups: custom-made mandibular advancement splints (MASs), prefabricated mandibular advancement devices (MADs), modified complete dentures, bite-raising appliances (BRAs), and tongue-retaining devices (TRDs). Conclusion: A wide variety of appliances have been proposed for snoring. MASs are the most frequently reported appliances, followed by TRDs. Current evidence sug-gests that these appliances are primarily effective in mild and moderate cases