A 58-year-old man presents with excessive fatigue and daytime sleepiness. After polysomnography, he is found to have severe obstructive sleep apnea.
Should oral appliances be considered a first-line treatment for obstructive sleep apnea?
Although oral appliances provide improved subjective sleepiness and sleep-disordered breathing, continuous positive airway pressure (CPAP) is more effective. Oral appliances should not be used as a first-line treatment but rather should be reserved for patients who cannot tolerate CPAP or who refuse to use it.1
Obstructive sleep apnea affects up to 4 percent of adults and leads to daytime sleepiness, low oxygen levels during sleep, pulmonary hypertension, systemic hypertension, right-sided heart failure, and arrhythmias.2 Daytime sleepiness can cause motor vehicle collisions, injuries at work, and poor work performance.3
Physicians should consider diagnostic testing for obstructive sleep apnea in patients who have apneas; awakening with a choking sensation; snoring; hypertension; daytime sleepiness; obesity; or a short, thick neck with a circumference greater than 16 inches in a woman or greater than 17 inches in a man.4 Many patients do not realize that they snore or have nocturnal arousals, but questioning a sleep partner may help suggest the diagnosis.5 Causes of obstructive sleep apnea include hypothyroidism, restrictive lung disease from scoliosis, and neuromuscular disorders such as postpolio syndrome.5 Diagnostic testing typically is with polysomnography. Overnight unattended oximetry is another option for patients at high risk who do not have access to a sleep laboratory.4
Treatment options for obstructive sleep apnea include behavioral changes (e.g., weight loss, good sleep hygiene, elimination of alcohol and sleep medications, sleeping on the side), CPAP, surgery, and oral appliances.4,6 Behavioral changes should be recommended for all patients with obstructive sleep apnea and may be sufficient treatment for those with mild disease.4
Background. Obstructive sleep apneahypopnea is a syndrome characterized by recurrent episodes of partial or complete upper airway obstruction during sleep that usually are terminated by an arousal. Nasal continuous positive airway pressure (CPAP) is the primary treatment for obstructive sleep apneahypopnea, but many patients are unable or unwilling to comply with this treatment. Oral appliances are an alternative treatment for sleep apnea.
Objectives. The objective was to review the effects of oral appliances in the treatment of sleep apnea in adults.
Search Strategy. The authors1 searched the Cochrane Airways Group Sleep Apnea RCT Register. Searches were current as of June 2004. Reference lists of articles also were searched.
Selection Criteria. Randomized trials comparing oral appliances with control or other treatments in adults with sleep apnea.
Data Collection and Analysis. Trial quality was assessed and two reviewers extracted data independently. Study authors were contacted for missing information.
Primary Results. Thirteen trials involving a total of 553 participants were included. All the studies had some shortcomings, such as small sample size, under-reporting of methods and data, and lack of blinding.
Oral appliances versus control appliances (five studies): Oral appliances reduced daytime sleepiness in two crossover trials (weighted mean difference [WMD] –1.81 [95% confidence interval (CI): –2.72 to –0.90]), and improved apnea-hypopnea index (–13.17 [–18.53 to –7.80] parallel group data—four studies).
Oral appliances versus CPAP (seven studies): Oral appliances were less effective than continuous positive pressure in reducing apnea-hypopnea index (WMD 13 [95% CI: 7.63 to 18.36], parallel studies—two trials; WMD 6.96 [4.82 to 9.10] crossover studies—six trials). However, no significant difference was observed on symptom scores. Nasal continuous positive pressure was more effective at improving minimum arterial oxygen saturation during sleep compared with oral appliances. In two small crossover studies, participants preferred oral appliance therapy to CPAP.
Oral appliances versus surgery (one study): Symptoms of daytime sleepiness were initially lower with surgery, but this difference disappeared at 12 months. Apneahypopnea index initially did not differ significantly, but did so after 12 months in favor of oral appliances.
Reviewers’ Conclusions. There is some evidence suggesting that oral appliance use improves subjective sleepiness and sleep-disordered breathing compared with a control. Nasal CPAP appears to be more effective in improving sleep-disordered breathing than oral appliances. Until there is more definitive evidence on the effectiveness of oral appliances, it would appear to be appropriate to restrict oral appliance therapy to patients with sleep apnea who are unwilling or unable to comply with CPAP therapy.
These summaries have been derived from Cochrane reviews published in the Cochrane Database of Systematic Reviews in the Cochrane Library. Their content has, as far as possible, been checked with the authors of the originalreviews, but the summaries should not be regarded as an official product of the Cochrane Collaboration; minorediting changes have been made to the text (http://www.cochrane.org).
Positive airway pressure devices are the most consistently successful and extensively studied treatment for obstructive sleep apnea.7 However, compliance is a concern because CPAP can be uncomfortable, can cause mucous membrane drying, and may induce claustrophobia. Modification of CPAP using bilevel pressure ventilation reduces the work of breathing, and some patients, especially those with chronic lung disease, find this more tolerable.8
Oral appliances, manufactured or fitted by a dentist or oral surgeon, are used to move the tongue or mandible forward. They help prevent the collapse of the tongue and soft tissues in the back of the throat to facilitate maintenance of an open airway without CPAP. Adverse effects of oral appliances include temporomandibular joint discomfort, bite change, and excessive salivation or dryness of the mouth. This Cochrane review1 did not address individual mandibular and tongue repositioning devices, a variety of which are on the market. It also was unable to break down the individual studies into smaller population subgroups because the populations were already heterogeneous. Despite these limitations, most of the studies included in this review showed similar results: oral appliances are a viable alternative for patients who are unwilling or unable to use CPAP, but appliances are not as effective as CPAP in the treatment of obstructive sleep apnea.
Finally, surgical modifications to the anatomy may be considered in patients with significant disease who want more invasive treatments after conservative measures have failed. Altering the uvula and soft palate, maxillomandibular advancement, genial tubercle and tongue advancement, and combinations of these may be performed, with or without improvement in sleep apnea. Surgery entails recovery time and is more appropriate for younger patients with severe apnea who are healthy enough to undergo these procedures.8 Bariatric surgery also may be considered as a treatment for patients with morbid obesity to help decrease the severity of obstructive sleep apnea.8 Controlled studies of any type of surgery to relieve symptoms of obstructive sleep apnea are lacking.9