Oral appliances, specifically mandibular advancement splints (MAS), arebecoming an increasingly popular and widely accepted treatment forsleep-disordered breathing. Polysomnographic recordings in RCTs havedemonstrated that customised appliances, particularly the titratableversions, can be highly effective in reducing snoring and obstructivesleep Apnoea (OSA) indices. A MAS may also be used as a precursor tomore complex orthognathic surgery.Continuous positive airway pressure (CPAP) has long been consideredas the ‘gold standard’ treatment for OSA. However, the efficacy of eitherCPAP or MAS involves not just the physical mode of action, but alsothe patient’s recognition of a therapeutic benefit that motivates themto use the device consistently. There is increasing evidence of patients’preference for MAS over tolerance of the CPAP alternative. Compliancefor both therapies relies substantially on appropriate clinical supportto help patients acclimatize to treatment and minimise undesirableside-effects. This presentation will highlight the development of thedental appliances, design features and the clinical management ofpotential side-effects to optimise MAS treatment outcomes.