Long-term effects of mandibular repositioning appliances on symptoms of sleep apnoea.

Mandibular repositioning appliances (MRAs) reduce symptoms of obstructive sleep apnoea in the short term, but the long-term effects are unknown. Our objective was to evaluate the long-term symptomatic effects of custom-made MRAs and to identify the patients who will experience subjective benefits from treatment. A cohort of 260 consecutive patients treated with appliances for non-apnoeic snoring or sleep apnoea was followed up by a questionnaire and examination after an average of 5.4 years. The subjective effect was defined as good when complaints of daytime sleepiness occurred less than once a week. A total of 185 patients (71%) responded to the questionnaires. Of the respondents, 96 reported frequent use, 33 reported infrequent use, 26 reported discontinued treatment and 30 reported modified treatment. Mild cases (apnoea-hypopnoea index [AHI] < 15) were likelier than more severe cases to continue treatment. Patients who had used MRAs reported fewer complaints of sleepiness, headaches and daytime naps. Frequent use (P = 0.001), few night-time awakenings before start of treatment (P = 0.02) and effective apnoea reduction during treatment of more severe cases (P = 0.02) correlated with a good subjective effect at long-term follow-up. Our conclusion is that custom-made MRAs reduce sleep apnoea symptoms in the long term. The mildest cases will experience the greatest long-term benefit. The reason is that non-apnoeic snorers and patients with a mild disease are more likely to continue treatment and that their long-term results with regard to excessive sleepiness are similar to patients with a more severe disease.