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July/August
2003 |
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Oral Appliance Therapy for
SBD
It is important for physicians in the field of sleep medicine
to consider oral appliance therapy as a treatment option for
patients with sleep-disordered breathing.
By Jeffrey Pancer, DDS
 Oral-appliance therapy has been available for a
century for the treatment of snoring. In 1903, Pierre Robin
described the monoblock for the treatment of glossoptosis. Today,
many oral appliances have been shown to be very effective in
correcting sleep-disordered breathing (SDB).1-13 The most
effective types of oral appliances now in use are categorized as
anterior mandibular positioners or tongue-retaining devices. The
former are much more popular than the latter. There are a few other
types of appliances available, but they are mainly of historical
significance.
The tongue-retaining device1 made its appearance around 1982.
This type of device uses suction to move the tongue forward, holding
it away from the back of the throat and opening the airway. The
tongue-retaining device has not been shown to be as well tolerated
(or as effective, in more severe cases) as the anterior mandibular
positioner.14 Patients are candidates for use of the
tongue-retaining device if they have dentures, fewer than eight
teeth per arch, periodontal disease, suspect fixed bridge work, or a
preference for pushing the tongue forward to open the airway.
Disadvantages of the tongue-retaining device are that it is
impossible for patients who gag easily to use it, that the patient
must have a patent nasal airway, that it cannot be made adjustable
(limiting the amount of space that can be created by moving the
tongue forward), and that patients may be unhappy with their
appearance while wearing the device.
The most common and most effective14 oral appliances
used today to treat SDB are anterior mandibular positioners. The
anterior mandibular positioner moves the lower jaw anteriorly.
Because the tongue is attached to the base of the lower jaw and to
the hyoid bone, this movement pulls the tongue away from the back of
the throat and lifts the hyoid bone, expanding the airway. To use
this type of device, the patient must have at least eight teeth per
arch that are structurally sound and in good periodontal health.
A good anterior mandibular positioner, fabricated to the
specifications of a dentist well trained in oral-appliance therapy,
may be used for all snorers and patients with obstructive sleep
apnea (OSA) who desire one, regardless of the severity of their
disorder. This does not mean that this appliance will work for all
patients. The patient’s level of SDB must be determined. If apnea is
present to any degree, the patient must undergo follow-up
polysomnography (PSG) (or, at a minimum, overnight pulse oximetry)
under the care of a sleep physician.
Very severe apnea often will not be reduced to acceptable levels
using an mandibular positioner. Although an excellent reduction in
apnea levels can usually be expected, hypopnea levels sometimes
remain unacceptably high. For this reason, follow-up care for
patients using these devices is of utmost importance.
Schmidt-Nowara et al2 indicated that it did not matter
which appliance was used; effectiveness would be the same. They
stated, “Despite considerable variations in design, the clinical
results are remarkably consistent. Snoring is improved in almost all
patients and is often eliminated. Mean results of studies show that
OSA improves in the majority of patients. Half of those patients who
improve achieve an apnea-hypopnea index (AHI) of <20, but as many
as 40% are left with notably elevated AHIs.”2 At the
time, appliances used in published studies3,4 were
nonadjustable, with the exception of the device studied by Clark et
al.5
At the Department of Medicine, Respiratory Division, St Michael’s
Hospital, University of Toronto, initial work with a new nonvariable
mandibular advancement appliance in 30 cases yielded moderate
success; results were promising, but inconsistent. A decision was
then made to do a study using an adjustable mandibular positioner to
determine whether some oral appliances used for SDB are more
effective than others. An appliance was decided on that would
control the position of the lower jaw completely and that could be
adjusted in the mouth during use. This appliance could be subject to
titration during PSG testing, ensuring the best possible results for
a given patient.
Study Design
In 1999, Pancer et
al7 showed that the effectiveness of oral-appliance
therapy was significant. This study was also the first to show
consistently the effectiveness of this type of therapy in treating
severe apnea patients.8 The study enrolled 134 patients.
Any patient who desired an oral appliance was accepted into the
study, regardless of the degree of SDB (which ranged from simple
snoring to very severe apnea, with the highest AHI in the study
being 115). The only patients who could not be accepted were those
lacking adequate dentition.
Of the 134 who started the study, 13 were lost to follow-up care.
Another 46 patients did not undergo follow-up PSG, but answered
questionnaires; 75 patients had baseline and follow-up PSG. Of 121
patients, 13 could not tolerate wearing the device and five who
could tolerate it could not achieve an adequate response. The
remaining 103 patients were determined to have positive follow-up
results.
The oral appliance was preferred to continuous positive airway
pressure (CPAP) by 99 patients. An additional four patients
preferred to use CPAP at home and the oral device for travel. The 46
patients who refused follow-up PSGs were mainly simple snorers who
had no apnea. The compliance of the other subjects was ensured
because, in Ontario, apnea patients must follow treatment requests
or be reported to the Ministry of Transportation, after which they
will lose their licenses to drive.
Findings
When the 75 patients who underwent
follow-up PSGs arrived for testing, the sleep laboratory staff was
asked to adjust each patient’s oral device to the most effective
position possible within that particular patient’s comfort range. In
most cases, this was the best result possible using an anterior
mandibular positioner. Raphaelson et al9 titrated therapy for six
patients in a similar manner in 1998.
At the Respiratory Division, St Michael’s Hospital, we found a
significant reduction in AHI, which fell from 44 ± 28 events/hour at
baseline to 12 ± 15 events per hour (P<0.0005) The arousal index
was reduced from 37 ± 27 events/hour to 16 ± 13 events/hour
(P<0.050) and the Epworth score fell from 11±5 to 7±3
(P<0.0005). The baseline assessments of subjects’ bed partners
indicated that 96% of patients snored loudly either “always” or
“often,” but only 2% were described as doing so while using the
dental device. This revealed a very significant improvement in
snoring.
Of the 75 subjects undergoing follow-up PSGs, 34 had AHIs of 40
or more. Of these, 16 were considered responders because their AHIs
decreased to fewer than 10. Patients unable to achieve this decrease
were considered nonresponders, but their average improvement was
63.6%.
Table 1 is from the article in Chest citing other factors
studied.7 Only AHI and arousal index, but not other
variables, were significantly reduced (P< 0.0005) with the
appliance, even in the nonresponders.
Side Effects
Common early side effects are
tooth discomfort, jaw or gum discomfort, excessive salivation, and
temporomandibular joint pain. Certain teeth may loosen if unusual
pressure is exerted. Over the long term, there may be some
tooth-position change, jaw-position change, or space opening between
the posterior teeth. These problems may require interceptive
therapies, such as the use of a leaf gauge or some type of
orthodontic therapy. For this reason, it is important to see the
patient annually.
Efficacy and Reimbursement
Good medicine
consists of using the least invasive effective technique that is
well tolerated by the patient. Oral appliances very often have been
shown to be as effective as CPAP7,12,16 at all levels of
severity; nonetheless, many health insurers cover CPAP, but not oral
appliances. The advantage of CPAP therapy is that it forces air into
the patient. If patients tolerated this therapy well, it would
unquestionably be the method of choice for treating all types of
apnea. However, CPAP is notorious for its poor acceptance by
patients, especially those with mild or moderate apnea who are
nonsymptomatic. With anterior mandibular positioners, the patient
must inhale actively. Patients in our study prefer oral appliances
to CPAP 20:17; 99 patients preferred oral appliances
given the choice, with four patients who had good results with an
oral appliance still preferring CPAP and using the oral appliance
only for traveling.7
Studies10,11 have shown that patients also comply
better with oral-appliance therapy. If oral appliances were offered
on a par with CPAP and prescribed as a very acceptable alternative
to CPAP therapy, insurance companies would have to fund oral
appliances in the same manner as CPAP. Costs of excellent oral
appliances vary from $1,000 to $2,000, a price range similar to that
of CPAP.
CPAP is, and should be, the main therapy for severe apnea
patients. In 1995, Schmidt-Nowara et al2 wrote, “Oral
appliances present a useful alternative, especially for patients
with simple snoring and others with moderate OSA who cannot tolerate
nasal CPAP.” Our study7 demonstrated an 87% positive
response across the board for snoring and an 81% positive response
for apnea, no matter what the severity level was. For these reasons,
if the patient desires an oral appliance, it should be available. If
patients are followed, as they should be for all SDB treatments,
when one type of therapy fails, another may commence. The key to
adequate therapy is follow-up care.
Qualified Sleep Dentists
Many physicians in
the field of sleep medicine are either unaware of the benefits of
oral appliance therapy or unaware of dentists having backgrounds in
this type of therapy. The Academy of Dental Sleep Medicine is an
international, nonprofit organization that promotes the education
and training of dental and medical professionals, as well as the
education of the public. The members of this organization
demonstrate an interest in this therapy. Credentialed members of
this body have exhibited an extra level of knowledge in sleep
medicine in general, as well as a proficiency in oral-appliance
therapy.
Jeffrey Pancer, DDS, practices dentistry in Toronto; a large
portion of his practice is devoted to oral-appliance therapy for
SDB. His study involving 134 patients with all levels of apnea using
oral appliance therapy for SDB was published in Chest, the journal
for the American College of Chest Physicians, and he has reviewed
numerous articles on SDB for that journal. A certified member of the
Academy of Dental Sleep Medicine (ADSM) and a member of its Board of
Directors, he is also chair of the Standards of Practice Committee
for the ADSM. He is a member of the American Academy of Sleep
Medicine and has just been named to its Standards of Practice
Committee.
References
1. Cartwright R, Samelson C. The
effects of a nonsurgical treatment for obstructive sleep apnea—the
tongue retaining device. JAMA. 1982;248:705.
2. Schmidt-Nowara
WW, Lowe A, Wiegand L, et al. Oral appliances for the treatment of
snoring and obstructive sleep apnea: a review. Sleep.
1995;18:501-510.
3. Soll BA, George PT. Treatment of obstructive
sleep apnea with a nocturnal airway patency appliance. N Engl J Med.
1985;313:386-387.
4. George PT. A modified functional appliance
for treatment of obstructive sleep apnea. Journal of Clinical
Orthodontics. 1987;21:171-175.
5. Clark GT, Arand D, Chung E, et
al. Effect of anterior mandibular positioning on obstructive sleep
apnea. Am Rev Respir Dis. 1993;147:624-629.
6. Thornton WK,
Roberts DH. Nonsurgical management of the obstructive sleep apnea
patient. J Oral Maxillofac Surg. 1996;54:1103-1108.
7. Pancer J,
Al-Faifi S, Al-Faifi M, Hoffstein V. Evaluation of variable
mandibular advancement appliance for treatment of snoring and sleep
apnea. Chest. 1999;116:1511-1518.
8. Lavie P. Treatment of sleep
apnea: unmet needs. Chest. 1999;116:1501-1503.
9. Raphaelson M,
Alpher E, Bakker K, et al. Oral appliance therapy for obstructive
sleep apnea syndrome: progressive mandibular advancement during
polysomnography. Cranio. 1998;16:44-50.
10. Ferguson KA, Ono T,
Lowe A, et al. A randomized crossover trial of an oral appliance vs
nasal-continuous positive airway pressure in the treatment of
mild-moderate obstructive sleep apnea. Chest.
1996;109:1269-1275.
11. Ferguson KA, Ono T, Lowe AA, et al. A
short term controlled trial of an adjustable oral appliance for the
treatment of mild to moderate obstructive sleep apnea. Thorax.
1997;52:362-368.
12. Menta A, Qian J, Petocz P, Darendeliler MA,
Cistulli PA. A randomized, controlled study of a mandibular
advancement splint for obstructive sleep apnea. Am J Respir Crit
Care Med. 2001;163:1457-1461.
13. Eveloff SE. Treatment of
obstructive sleep apnea no longer just a lot of hot air. Chest.
2002;121:674-677.
14. Loube DI, Strauss AM. Survey of oral
appliance practice among dentists treating obstructive sleep apnea
patients. Chest. 1997;111:382-386.
15. Barbe F, Mayoralas LR,
Duran J, et al. Treatment with continuous positive airway pressure
is not effective in patients with sleep apnea but no daytime
sleepiness. Ann Intern Med. 2001;134:1015-1023.
16. Henke KG,
Frantz DE, Kuna ST. An oral elastic mandibular advancement device
for obstructive sleep apnea. Am J Respir Crit Care Med.
2000;161:420-425. |
