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Oral appliance treatment of obstructive sleep apnea: an update.
Current Opinion in Pulmonary Medicine. November 2009 - Volume 15 - Issue 6 - p 591-596. Chan, Andrew SL; Cistulli, Peter A


Oral appliances are an alternative to continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea (OSA). Although CPAP is a highly efficacious treatment, there is a need for other treatment options because the clinical effectiveness of CPAP is often limited by poor patient acceptance and tolerance, and suboptimal compliance.There has been an expansion of the research evidence to support the use of oral appliances in clinical practice. Recent work has focused on the following clinically relevant areas: the effect of device design on efficacy and patient compliance, the role of different modalities for assessing the upper airway in the prediction of treatment outcome, the assessment of the impact of treatment on a range of health outcomes and the evaluation of long-term adverse effects.

There is robust evidence of the efficacy of oral appliances for improving polysomnographic indices and modifying the health risk associated with OSA. The current evidence suggests a similar impact on health outcomes as CPAP. However, further research is required to address a number of unresolved issues, including the influence of device design, titration procedures, prediction of treatment outcome and the clinical effectiveness of oral appliances for modifying the adverse health consequences of OSA.

Oral Appliance Therapy Improves Symptoms in Obstructive Sleep Apnea
Helen Gotsopoulos, Carol Chen, Jin Qian and Peter A. Cistulli

Department of Respiratory Medicine, Centre for Sleep Disorders and Respiratory Failure, St. George Hospital, University of New South Wales, Kogarah, Australia


The aim of this study was to evaluate the effect of a mandibular advancement splint (MAS) on daytime sleepiness and a range of other symptoms in obstructive sleep apnea (OSA). Using a randomized crossover design, patients received 4 weeks of treatment with MAS and a control device (inactive oral appliance), with an intervening 1-week washout. At the end of each treatment period, patients were reassessed by questionnaire, polysomnography, and multiple sleep latency test. Fifty-nine men and 14 women with a mean (± SD) age of 48 ± 11 years and proven OSA experienced a significantly improved mean (± SEM) sleep latency on the multiple sleep latency test (10.3 ± 0.5 versus 9.1 ± 0.5 minutes, p = 0.01) and Epworth sleepiness scale score (7 ± 1 versus 9 ± 1, p < 0.0001) with the MAS compared with the control device after 4 weeks. The proportion of patients with normal subjective sleepiness was significantly higher with the MAS than with the control device (82 versus 62%, p < 0.01), but this was not so for objective sleepiness (48 versus 34%, p = 0.08). Other OSA symptoms were controlled in significantly more patients with the MAS than with the control device. MAS therapy improves a range of symptoms associated with OSA. This study has shown that 4 weeks of MAS therapy improves daytime sleepiness and a range of other symptoms associated with OSA. This study extends our previous findings, confirming the efficacy of MAS therapy in controlling OSA in a substantial number of patients, including those with moderate and severe OSA.

The Efficacy of Oral Appliances in Obstructive Sleep Apnea. Anita A. Shah, DO, Christopher J. Lettieri, MD, Aaron B. Holley, MD and Jeffery A. Mikita, MD. Walter Reed Army Medical Center, Washington, DC. November 3, 2009. American College of Chest Physicians Conference 2009.


Continuous positive airway pressure (CPAP) is the treatment of choice for most patients with obstructive sleep apnea (OSA). Oral appliances (OA) are indicated as a treatment option for mild OSA, but are not typically used in patients with more severe disease due to a lack of perceived benefit and concerns for high failure rates. CPAP may hinder military service and patients with OSA are often referred for OA therapy regardless of disease severity. The purpose of this study was to determine the efficacy of OAs in ablating obstructive events in a wide spectrum of disease severity. Retrospective review of consecutive adult patients diagnosed with OSA between 2000 and 2005 undergoing polysomnographic and OA titrations. We recorded demographic and polysomnographic data on all patients. The primary endpoint was the rate of successful OA titrations. Intolerance or a residual apnea-hypopnea index (AHI) > 5 was considered a treatment failure. 638 patients were included. 86.5 % were male. Mean age, AHI and BMI were 41.7±9.2, 30.2±24.9, and 28.7±4.5 respectively. Disease severity was stratified as mild (n=226), moderate (n=187) and severe (n=225). 162 (25.4%) of patients were intolerant to OA. Overall, OA were successful in 49.8% patients. OA were successful in 65.3% with mild, 49.6% with moderate and 35.1% with severe disease. 24.8% of patients had an unsuccessful titration. Patients with a BMI greater than 29.3 and a SpO2 below 90% for at least 7.8% of the night were less likely to normalize their AHI (p=0.004, p<0.001 respectively).OA can be an effective treatment for OSA. While OA are more effective in patients with mild disease, those with moderate to severe disease may also benefit and should not be excluded from this therapeutic option. OA may provide an alternate treatment option for military service members with OSA who are intolerant to CPAP or require therapy in an austere deployed setting.

Oral appliance therapy reduces blood pressure in obstructive sleep apnea: a randomized, controlled trial.
Gotsopoulos H, Kelly JJ, Cistulli PA.
Department of Respiratory & Sleep Medicine, St George Hospital, The University of New South Wales, Sydney Australia. Sleep. 2004 Aug 1;27(5):934-41.


STUDY OBJECTIVE: To investigate the short-term effect (4 weeks) of oral appliance therapy for obstructive sleep apnea on blood pressure. DESIGN: Randomized, controlled, crossover trial. SETTING: Multidisciplinary sleep disorders clinic in a university teaching hospital. PATIENTS: Sixty-one patients diagnosed with obstructive sleep apnea on polysomnography (apnea hypopnea index > or = 10 per hour and at least 2 of the following symptoms--daytime sleepiness, snoring, witnessed apneas, fragmented sleep; age > 20 years; and minimum mandibular protrusion of 3 mm). INTERVENTION: A mandibular advancement splint (MAS) and control oral appliance for 4 weeks each. MEASUREMENTS AND RESULTS: Polysomnography and 24-hour ambulatory blood pressure monitoring were carried out at baseline and following each 4-week intervention period. Patients showed a 50% reduction in mean apnea hypopnea index with MAS compared with the control and a significant improvement in both minimum oxygen saturation and arousal index. There was a significant reduction with the MAS in mean (+/- SEM) 24-hour diastolic blood pressure (1.8 +/- 0.5 mmHg) compared with the control (P = .001) but not in 24-hour systolic blood pressure. Awake blood-pressure variables were reduced with the MAS by an estimated mean (+/- SEM) of 3.3 +/- 1.1 mmHg for systolic blood pressure (P = .003) and 3.4 +/- 0.9 mmHg for diastolic blood pressure (P < .0001). There was no significant difference in blood pressure measured asleep. CONCLUSION: Oral appliance therapy for obstructive sleep apnea over 4 weeks results in a reduction in blood pressure, similar to that reported with continuous positive airway pressure therapy.

Oral Appliances for Snoring and Obstructive Sleep Apnea: A Review
Kathleen A. Ferguson, MD1; Rosalind Cartwright, PhD2; Robert Rogers, DMD3; Wolfgang Schmidt-Nowara, MD4
1Division of Respirology, University of Western Ontario, London, Ontario, Canada, 2Department of Behavioral Sciences, Rush University Medical Center,Chicago, IL, 3Department of Dental Medicine, St. Barnabas Medical Center, Gibsonia, PA, 4University of Texas Southwestern, Sleep Medicine Associatesof Texas, Dallas, TX


We conducted an evidence-based review of literature regarding use of oral appliances (OAs) in the treatment of snoring and obstructive sleep apnea syndrome (OSA) from 1995 until the present. Our structured search revealed 141 articles for systematic scrutiny, of which 87 were suitable for inclusion in the evidence base, including 15 Level I to II randomizedcontrolled trials and 5 of these trials with placebo-controlled treatment. The efficacy of OAs was established for controlling OSA in some but not all patients with success (defined as no more than 10 apneas or hypopneas per hour of sleep) achieved in an average of 52% of treatedpatients. Effects on sleepiness and quality of life were also demonstrated, but improvements in other neurocognitive outcomes were not consistent. The mechanism of OA therapy is related to opening of the upper airway as demonstrated by imaging and physiologic monitoring. Treatment adherence is variable with patients reporting using the appliance a median of 77% of nights at 1 year. Minor adverse effects were frequent whereas major adverse effects were uncommon. Minor tooth movement and small changes in the occlusion developed in some patients after prolonged use, but the long-term dental significance of this is uncertain. In comparisonto continuous positive airway pressure (CPAP), OAs are less efficacious in reducing the apnea hypopnea index (AHI), but Oral Appliances appear to be used more (at least by self report), and in many studies were preferred over CPAP when the treatments were compared. Oral Appliances have also been compared favorably to surgical modification of the upper airway (uvulopalatopharyngoplasty, UPPP). Comparisons between OAs of different designs have produced variable findings. The literature of Oral Appliances therapy for OSA now provides better evidence for the efficacy of this treatment modality and considerable guidance regarding the frequency of adverse effects and the indications for use in comparison to CPAP and UPPP.

Oral Appliance Therapy for Obstructive Sleep Apnea
Ng, Andrew1; Gotsopoulos, Helen1; Darendeliler, Ali M.2; Cistulli, Peter A.3
Treatments in Respiratory Medicine, Volume 4, Number 6, 2005 , pp. 409-422(14)


Obstructive sleep apnea (OSA) is a common disorder characterized by repetitive, complete or partial closure of the upper airway during sleep, resulting in sleep fragmentation and oxygen desaturation. The disorder causes significant morbidity, particularly in terms of impairment of daytime functioning and the impact this has on quality of life. There is also evidence that links OSA to long-term cardiovascular morbidity, including hypertension, myocardial infarction, and stroke, and increased risk of motor vehicle accidents. There is clear evidence that effective treatment of OSA provides major benefit to patients.
Nasal continuous positive airway pressure (CPAP) is the current treatment of choice, but its cumbersome nature makes tolerance and compliance less than optimal. This gives rise to the need for other alternatives that are equally effective, but more tolerable. There is growing interest in the use of oral appliances to treat snoring and OSA. The rationale is that advancement of the mandible and tongue impacts positively on upper airway caliber and function. There are many such types of appliances, and they have potential advantages over CPAP in that they are unobtrusive, make no noise, do not need a power source, and are potentially less costly.

There is a growing evidence base to support the use of oral appliances in the management of OSA. Recent evidence from randomized controlled trials indicates that oral appliance therapy is effective in controlling OSA in up to 50% of patients, including some patients with more severe forms of OSA. This is associated with a significant improvement in symptoms, including snoring and daytime sleepiness. This evidence is strong for short term, and emerging for long-term treatment of OSA with oral appliances. Whilst direct comparisons with CPAP indicate the superiority of CPAP overall, similar outcomes between the two treatments appear to be achieved in a substantial subgroup of patients. Patient acceptance has, in general, been in favor of oral appliances.

Notwithstanding the expanding role of oral appliance therapy, there are a number of limitations that are yet to be overcome. Key issues include the inability to reliably predict treatment outcome, the apparent need for an acclimatization period to attain maximal efficacy of treatment, uncertainty about selection of the appropriate 'dosage' of mandibular advancement required to control OSA in the individual patient, uncertainty about the influence of appliance design on treatment outcome and adverse effects, adherence to treatment, and potential long-term complications of therapy. These issues require resolution before oral appliance therapy can surpass CPAP as first-line treatment for OSA.

Efficacy of Positive Airways Pressure and Oral Appliance in Mild to Moderate ObstructiveSleep Apnea. Maree Barnes, R. Douglas McEvoy, Siobhan Banks, Natalie Tarquinio, Christopher G. Murray, Norman Vowles, and Robert J. Pierce. Dr. Maree Barnes, Institute for Breathing and Sleep, Austin Health, Studley Road, Heidelberg, 3084, Victoria, Australia.


The efficacy of currently-recommended treatments is uncertain in patients with mild to moderateobstructive sleep apnea (apnea-hypopnea index 5-30). A group of 114 sleep clinic patients withapnea-hypopnea index 5-30 have participated in a randomized controlled crossover trial of 3Month's treatment with each of nasal continuous positive airways pressure, a mandibularadvancement splint and a placebo tablet. Outcomes were sleep fragmentation and hypoxemia,daytime sleepiness, quality of life, neurobehavioral function and blood pressure. Both activetreatments improved sleep outcomes, but positive airways pressure had a greater effect. Quality of life, symptoms and subjective but not objective sleepiness improved to a similar degree with both treatments, however many of the improvements seen in neuropsychological function and mood were not better than the placebo effect. Some aspects of nocturnal blood pressure were improved with the splint but not with continuous positive airways pressure. This study has shown that although both continuous positive airways pressure and mandibular advancement splint effectively treated sleep-disordered breathing and sleepiness, the expected response in neurobehavioral function was incomplete. This may be due to the splint having a lesser therapeutic effect and continuous positive airways pressure being poorly tolerated and therefore used less in this patient group.

A comparison of responders and nonresponders to oral appliance therapy for the treatment of obstructive sleep apnea. R Otsuka, FR de Almeida, AA Lowe, F RyanAmerican Journal of Orthodontics and Dentofacial Orthopedics, Volume 129


This retrospective study compared cephalometric variables between responders and nonresponders to a titratable oral appliance (OA) in a group of subjects matched for sex, pretreatment age, and body mass index (BMI). Methods: Nine nonresponders as defined by an improvement in the apnea hypopnea index (AHI; <20%) and their individually matched responders were selected for this study. The difference in age for each matched pair was ±5 years, and, for BMI, the difference was ±15%. The pretreatment AHI was matched to the same category (moderate, >15 to ?30; severe I, >30 to ?45; and severe II, >45 AHI). Results: Middle and inferior airway space and oropharyngeal airway cross-sectional area were significantly larger in the nonresponders. Position of the mandible relative to the cervical spine was the only significant skeletal variable and was larger in nonresponders. Changes in BMI between the groups were statistically significant; the averages were a 2.9% increase in the nonresponders and a 0.5% decrease in responders. The wider airway in nonresponders might reflect an enhanced neuromuscular compensation while awake. The weight gain in nonresponders was relatively small, but it might have reduced the effectiveness of the OA. Conclusion: When treating OSA patients with OA therapy, clinicians should pay particular attention to airway size and weight changes.

Cost-effectiveness of oral appliances in the treatment of obstructive sleep apnoea-hypopnoea. Mohsen Sadatsafavi, Carlo A. Marra, Najib T. Ayas, John Stradling and John Fleetham. Sleep and Breathing, Volume 13, Number 3 / August, 2009


Oral appliances (OA) are commonly prescribed for the treatment of obstructive sleep apnoea-hypopnoea (OSAH), but there is limited evidence on their cost-effectiveness. A model was designed to simulate the costs and benefits of treatment of OSAH with OA or continuous positive airway pressure (CPAP) based on their effects on quality of life, motor vehicle crashes, and cardiovascular effects. The primary outcome was the incremental cost-effectiveness ratio (ICER) in terms of costs per one quality-adjusted life year (QALY) gained 5 years after treatment. Compared with no treatment, OA results in $268 higher costs and an incremental QALY of 0.0899 per patient (ICER?=?$2,984/QALY). Compared with OA, CPAP resulted in $1,917 more costs and 0.0696 additional QALYs (ICER?=?$27,540/QALY). For the most part in the sensitivity analyses, CPAP remained cost-effective compared to OA, and OA remained cost-effective with respect to no treatment in almost all scenarios. OAs are less economically attractive than CPAP but remain a cost-effective treatment for patients who are unwilling or unable to adhere to CPAP therapy.

The Effect of Oral Appliance Therapy on Obstructive Sleep Apnea C. ISHIKAWA, T. OGAWA, Y. SHIGETA, S. HIRAI, E. ANDO, T. IKAWA, T. HOSOI, S. FUKUSHIMA, K. MORII, K. IHARA, N. KAWAMURA, Y. MIZUNO, and J. NEJIMA.Tsurumi University, Yokohama, Japan, School of Dental Medicine, Yokohama, Japan


The study involved 80 OSA patients who were recruited from April 2005-October 2007. We prepared OA for 22 patients. The Post-PSG results were as follows: remarkable effect in 12 cases (55%), effective in 4 cases (18%) and non-effective in 6 cases (27%). 85% of patients reported they slept very well. However some side-effects were reported, headache (10%), TMJ or teeth pain (10%). Over all, patient satisfaction with OA was high, with only an occasional report of drooling or excessive dryness. Of the 22 patients who completed the questionnaire, 70% reported the OA as either remarkable or effective. Subsequently, the OA was a successful treatment option for OSA patients.