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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
JEFFREY PANCER, DDS; SALEM AL-FAIFI, MD; MOHAMED AL-FAIFI, MD AND
VICTOR HOFFSTEIN, PhD, MD, FCCP
* 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: firstname.lastname@example.org
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
OKSENBERG A, SILVERBERG DS,
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.