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Custom Made Dental Sleep Appliance- Bringing peace to the home

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Evaluation of Variable Mandibular Advancement Appliance for Treatment of Snoring and Sleep Apnea*
(Chest. 1999;1 16:1511-1518.) @ 1999 American College of Chest Physicians


* From the Department of Medicine, Respiratory Division, St. Michael's Hospital, University of Toronto, Ontario, Canada.

Correspondence to: Victor Hoffstein, PhD, MD, FCCP, St. Michael's Hospital, 30 Bond St, Toronto, Ontario, Canada M 5 B I W8; e-mail:

Objective: To evaluate an adjustable mandibular positioning appliance for treatment of snoring and sleep apnea.

Methods: One hundred thirty-four patients with baseline apnea/hypopnea index (AHI) of 37 ± 28 events/h (mean ± SD) received the appliance. The efficacy of the appliance was assessed by the following investigations, performed at baseline and with the appliance: polysomnography, Epworth sleepiness scale, bedpartners' assessment of snoring severity, patients' assessment of side effects, and overall satisfaction.

Results: Thirteen patients were lost to follow-up. Additional 46 patients had no follow-up polysomnography, but answered the questionnaires. A total of 75 patients had polysomnography at baseline and with the appliance. We found a significant reduction in AHI from 44 ± 28 events/h to 1 2 ± 1 5 events/h (p < 0.0005) and a reduction in the arousal index from 37 ± 27 events/h to 1 6 ± 1 3 events/h (p < 0.05). Epworth scores fell from II ± 5 to 7 ± 3 (p < 0.0005). Bedpartners' assessment revealed marked improvement in snoring. For example, at baseline 96% of patients were judged to snore loudly 'often' or 'always' by their bedpartners, whereas only 2% were judged so while using dental appliance. The most frequent side effect was teeth discomfort, present 'sometimes' or often' in up to 32% of patients. Follow-up clinical assessment in 1 21 patients conducted on the average 350 days after the insertion of the appliance revealed that 86% of patients continued to use the appliance nightly; 60% were very satisfied with the appliance, 27% were moderately satisfied, 11% were moderately dissatisfied, and 2% were very dissatisfied.

Conclusion: We conclude that the adjustable mandibular positioning appliance is an effective treatment alternative for some patients with snoring and sleep apnoea.

Effect of Oral Appliance Therapy on Upper Airway Collapsibility in Obstructive Sleep Apnea
Andrew T Ng, Helen Gotsopoulos, Jin Qian and Peter A Cistulli

Department of Respiratory and Sleep Medicine, St. George Hospital, University of New South Wales, Sydney, Australia

Correspondence: Correspondence and requests for reprints should be addressed to Peter Cistulli, M.D., Ph.D., Department of Respiratory Medicine, St. George Hospital, Belgrave Street, Kogarah, NSW 2217, Australia. E-mail:

Oral appliance therapy is emerging as an alternative to continuous positive airway pressure for the treatment of obstructive sleep apnea (OSA). However, its precise mechanisms of action are yet to be defined. We examined the effect of a mandibular advancement splint (MAS) on upper airway collapsibility during sleep in OSA. Ten patients with proven OSA had a custom-made MAS incrementally adjusted during an acclimatization period until the maximum comfortable limit of mandibular advancement was reached. Polysomnography with the splint was then performed. After a 1-week washout period, upper airway closing pressures during sleep (with and without MAS) were determined. Significant improvements with MAS therapy were seen in the apnea/hypopnea index (25.0 ± 3.1 vs. 13.2 ± 4.5/hour, p < 0.03) and upper airway closing pressure in Stage 2 sleep (–1.6 ± 0.4 vs. –3.9 ± 0.6 cm H2O, p < 0.01) and in slow wave sleep (–2.5 ± 0.7 vs. –4.7 ± 0.6 cm H2O, p < 0.02) compared with no therapy. These preliminary data indicate that MAS therapy is associated with improved upper airway collapsibility during sleep. The mediators of this effect remain to be determined.

(TERM: supine is when a person is lying on their back)

The effect of body posture on sleep-related breathing disorders: facts and therapeutic implications.
Sleep Medicine Reviews 1998;2(3):139-162


The aggravating effect of the supine body position on breathing abnormalities during sleep was recognized from the earliest studies on sleep breathing disorders. Most of the anatomical and physiological correlates of this phenomenon appear to be due to the effect of gravity on the upper airway. Although few articles have been published on this topic, it has been shown in a large population of obstructive sleep apnoea (OSA) patients that more than half of them are Positional Patients, i.e. they have at least twice as many apnoeas/hypopnoeas during sleep in the supine posture as in the lateral position. This positional phenomenon is influenced by factors such as Respiratory Disturbances Index (RDI), Body Mass Index (BMI), age and sleep stages. The sleep supine posture not only increases the frequency of the abnormal breathing events but also their severity. This sleep posture also has a detrimental effect on snoring, -as well as on the optimal CPAP pressure. Positional Therapy, i.e. the avoidance of the supine posture during sleep, is a simple behavioural therapy for many mild to moderate OSA patients. Unfortunately, only a few studies, including only a few patients, have investigated this form of therapy. Although the results of these studies are promising, the lack of a reliable long-term evaluation of its efficacy is perhaps an important reason why this form of therapy has not been widely accepted. Since mild to moderate OSA patients are the majority of the OSA patients and since without treatment, a large percentage of them will develop a more severe form of the disease, a thorough evaluation with a major emphasis on the long-term effectiveness of this form of therapy is urgently needed. Copyright 1998 W. B. Saunders Company Ltd. All rights reserved.