Mandibular advancement appliances and obstructive sleep apnoea: a randomized clinical trial. A short-term controlled trial of an adjustable oral appliance for the treatment of mild to moderate obstructive sleep apnoea.
This randomized placebo-controlled cross-over trial assessed the effectiveness of a mandibular advancement appliance (MAA) in managing obstructive sleep apnoea (OSA). Twenty-one adults, with confirmed OSA, were provided with a maxillary placebo appliance and a MAA for 4-6 weeks each, in a randomized order. Questionnaires at baseline and after each appliance assessed bed-partners' reports of snoring severity (loudness and number of nights per week), and patients' daytime sleepiness (Epworth Sleepiness Score, ESS). The Apnoea Hypopnoea Index (AHI) and Oxygen Desaturation Index (ODI) were measured at baseline and with each appliance during single night sleep studies. Seventy-nine per cent of subjects wore their MAA for at least 4 hours at night. Sixty-eight per cent of subjects wore their MAA for 6-7 nights per week. Excessive salivation was the most commonly reported complication. One subject was unable to tolerate the MAA and withdrew from the study. Among the remaining 20 subjects, the MAA produced significantly lower AHI and ODI values than the placebo. However, although the reported frequency and loudness of snoring and the ESS values were lower with the MAA than the placebo, these differences were not statistically significant. When wearing the MAA, 35 per cent of the OSA subjects had a reduction in the pre-treatment ODI to 10 or less, while 33 per cent had an AHI of 10 or less. The MAA was less effective in the subjects with the most severe OSA (pre-treatment ODI > 50 and/or pre-treatment AHI > 50). Although oral appliances are effective in some patients with obstructive sleep apnoea (OSA), they are not universally effective. A novel anterior mandibular positioner (AMP) has been developed with an adjustable hinge that allows progressive advancement of the mandible. The objective of this prospective crossover study was to compare efficacy, side effects, patient compliance, and preference between AMP and nasal continuous positive airway pressure (nCPAP) in patients with symptomatic mild to moderate OSA.
                Twenty four patients of mean (SD) age 44.0 (10.6) years were recruited with a mean (SD) body mass index of 32.0 (8.2) kg/m2, Epworth sleepiness score 10.7 (3.4), and apnoea/hypopnoea index 26.8 (11.9)/hour. There was a two week wash-in and a two week wash-out period and two treatment periods (AMP and nCPAP) each of four months. Efficacy, side effects, compliance, and preference were evaluated by a questionnaire and home sleep monitoring.
                One patient dropped out early in the study and three refused to cross over so treatment results are presented on the remaining 20 patients. The apnoea/hypopnoea index (AHI) was lower with nasal CPAP 4.2 (2.2)/hour than with the AMP 13.6 (14.5)/hour (p < 0.01). Eleven of the 20 patients (55%) who used the AMP were treatment successes (reduction of AHI to < 10/hour and relief of symptoms), one (5%) was a compliance failure (unable or unwilling to use the treatment), and eight (40%) were treatment failures (failure to reduce AHI to < 10/hour and/or failure to relieve symptoms). Fourteen of the 20 patients (70%) who used nCPAP were treatment successes, six (30%) were compliance failures, and there were no treatment failures. There was greater patient satisfaction with the AMP (p < 0.01) than with nCPAP but no difference in reported side effects or compliance.
                AMP is an effective treatment in some patients with mild to moderate OSA and is associated with greater patient satisfaction than nCPAP.
A single small study has found a short-term beneficial effect on the AHI in children with mild to moderate OSA. However, long-term safety and efficacy data are not available yet. Further RCTs are needed to evaluate anti-inflammatory drugs for OSA in children.