A follow-up study of dental and skeletal changes associated with mandibular advancement splint use in obstructive sleep apnea.

INTRODUCTION: Mandibular advancement splints (MAS) are a recognized therapeutic option in the treatment of obstructive sleep apnea (OSA). This study aimed to investigate side effects and possible changes in the dentofacial complex associated with long term use of MAS. METHODS: The sample included 64 patients with OSA who had been using MAS on average for 25.1 +/- 11.8 months (range, 10.7-64.5 months). A specifically designed questionnaire was used to investigate the patients' self-assessment of the side effects of wearing MAS; cephalometric analyses and dental cast measurements were conducted to identify objectively dental and skeletal changes caused by MAS over time. RESULTS: The most commonly reported side effects were jaw discomfort, tooth tenderness, excessive salivation, and dry mouth. Subjectively, snoring improved in 56 patients (88%), and daytime sleepiness (Epworth sleepiness scale) scores significantly decreased from pretreatment to follow-up (11.4-7.1, P <.001). Small subjective occlusal changes were experienced by 8 patients (12.5%). Reductions in overbite (-0.3 +/- 0.08 mm, P <.01) and overjet (-0.2 +/- 0.06 mm, P <.05) were found, and cephalometric analysis showed statistically significant but clinically insignificant changes limited to anterior movement of the mandibular incisors (0.5 +/- 0.12 mm, P <.001). CONCLUSIONS: Side effects of MAS use over long periods are common but mild and well tolerated by most patients, and dentofacial changes are negligible.

Oral appliance therapy for obstructive sleep apnea.

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.

Treatment of snoring and obstructive sleep apnea with mandibular repositioning appliances.

Snoring and obstructive sleep apnea form part of a spectrum of sleep disordered breathing affecting a significant proportion of the general population and particularly the middle aged. The consequences can be severe and even life threatening for both the individual directly affected and those more remotely involved. Adverse sequelae can manifest themselves acutely or in the longer term as a result of obstructive breathing induced hypersomnolence, neurocognitive deficits and cardiovascular abnormalities. The combination of anatomical and neuromuscular risk factors in the pathogenesis of OSA has resulted in a varied approach to its management. One such treatment option is mandibular repositioning appliances (MRA), which mechanically stabilize the airway. Whilst the efficacy of this simple intervention has been rigorously proven quite recently in a significant proportion of patients with varying disease severity, individual patient selection in its application remains uncertain. Short-term side-effects are common but usually transient, whilst in the long-term minor permanent adverse developments on the dentition and occlusion have been reported. Considering both the medicolegal implications of snoring and OSA and the increasing popularity of MRA, it is recommended that skilled multidisciplinary respiratory and dental personnel form the primary care team.

Oral appliance therapy reduces blood pressure in obstructive sleep apnea: a randomized, controlled trial.

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.

Effect of oral appliance therapy on upper airway collapsibility in obstructive sleep apnea.

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.

Effect of vertical dimension on efficacy of oral appliance therapy in obstructive sleep apnea.

The aim of this study was to assess the effect of bite opening induced by a mandibular advancement splint (MAS) on efficacy and side effects in the treatment of obstructive sleep apnea. In a randomized crossover fashion, 23 adult patients received either MAS-1 (4 mm of interincisal opening) or MAS-2 (14 mm of interincisal opening) for 2 weeks, followed by the alternate treatment for 2 weeks, with an intervening 1-week washout. Complete response was defined as a resolution of symptoms and a reduction in apnea/hypopnea index (AHI) to less than 5 per hour. Partial response was defined as improved symptoms and a reduction in AHI of 50% or more, with the AHI remaining at a value of 5 or more per hour. Both MAS-1 and MAS-2 produced similar reductions in mean (+/- SEM) AHI from baseline: 21 +/- 2 versus 8 +/- 1/hour and 21 +/- 2 versus 10 +/- 2/hour, respectively (p < 0.001). Either complete response or partial response occurred in 74 and 61% of patients with MAS-1 and MAS-2, respectively. Subjective improvements were reported with both appliances by the majority of patients. Patients preferred MAS-1 (78 versus 22%, p = 0.007). This study suggests that the amount of bite opening induced by MAS does not have a significant impact on treatment efficacy but does have an impact on patient acceptance.

Oral appliance therapy improves symptoms in obstructive sleep apnea: a randomized, controlled trial.

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.