Obligatory nasal breathing: effects on snoring and sleep apnoea

Objective: To test the effects on snoring and sleep disordered breathing of a dental prosthesis (Snore-No-More) which is designed to decrease snoring by preventing mouth breathing during sleep. Design: A crossover controlled trial. Each subject was studied on two nights a week apart. There was a control (no treatment) night and an experimental (treatment) night. The order of control and experimental nights was randomised. Setting: The Royal Adelaide Hospital Sleep Laboratory. Participants: Fourteen male volunteers (age range, 36-59 years) were studied. All had a history of chronic snoring but denied other symptoms of obstructive sleep apnoea syndrome. Interventions: On experimental nights subjects wore the dental prosthesis for the whole study period. On control nights no device was worn. Main outcome measures: Studies were conducted overnight during the subject's normal sleep period. The following measurements were made: (i) frequency and loudness of snores; (ii) frequency of disordered breathing events (apnoeas and hypopnoeas); (iii) mean and minimum arterial oxygen saturation while asleep; and (iv) sleep stages. Results: The dental prosthesis did not change the mean frequency or mean intensity of snores. The number of sleep disordered breathing events per hour of sleep decreased by approximately one-third on experimental nights (mean ± SEM events/h: control, 24.7 ± 5.3; experimental, 16.1 ± 3.3, P < 0.05). Neither sleep architecture nor arterial oxygen saturation differed between control and experimental nights. Conclusion: Snorers using the dental prosthesis Snore-No-More to produce obligatory nasal breathing are unlikely to experience clinical benefit.