A mandibular advancement device reduces sleep disordered breathing in patients with congestive heart failure

Sleep disordered breathing (SDB) including obstructive and central sleep apnoea/hypopnoea as well as periodic breathing (PB) is common and is believed to increase risk for mortality in patients with congestive heart failure (CHF). Mandibular advancement device (MAD) has widely been recommended for treatment of obstructive sleep apnoea but the method has never been investigated for treatment of SDB in the patients with CHF. The aim with the present study was to examine the effect of MAD intervention on SDB in patients with CHF. The study included 17 male patients, aged 68.4+/-5.7 (mean+/-SD) with stable, mild to moderate CHF due to left ventricular systolic dysfunction and with SDB, expressed as apnoea/hypopnoea index (AHI) > or = 10. The SDB was examined during a single night using an unattended, portable polysomnographic device in the patients home, prior to and following intervention with a individually adjusted MAD. The SDB was evaluated by calculating AHI, PB expressed as the percentage of the total registration time, oxygen desaturation index (ODI) and snoring time. The AHI was reduced by MAD intervention from 25.1+/-9.4 to 14.7+/-9.7 (p=0.003). ODI reduced from 21.1+/-9.0 to 10.5+/-7.8 (p=0.007) and snoring time decreased from 53+/-111 to 18+/-47 seconds (p=0.02). PB was reduced from 55.7+/-25.6 to 40.4+/-26.4 per cent without statistical significance. In conclusion, the MAD intervention may be a feasible method for reducing SDB in patients with stable, mild to moderate CHF and left ventricular systolic dysfunction.     

Sleep apnoea in patients with stable congestive heart failure an intervention study with a mandibular advancement device

In patients with congestive heart failure (CHF), sleep disordered breathing (SDB)--including obstructive and central sleep apnoea as well as periodic breathing--is a common condition and is believed to increase the risk of mortality. Treatment of SDB is considered important in the management of CHF. Improvements in SDB have a positive effect on cardiac output, measured with left ventricular ejection fraction (LVEF); on neurohormonal activity, measured as brain natriuretic peptide (BNP); and on the quality of life. Continuous positive airway pressure has been the traditional method used to treat SDB in patients with CHF, but compliance and tolerability are poor. A mandibular advancement device (MAD) is a dental device recommended for the treatment of sleep apnoea, but the method has never been evaluated in patients with CHF. The aims of the present studies were to evaluate the practical use of the MAD for the treatment of SDB in patients with CHF and to test the hypothesis that this intervention increases the dimensions of the pharyngeal airway (PAW), reduces SDB and BNP, and improves LVEF and the quality of life. Patients with mild to moderate CHF and SDB were evaluated using a portable polysomnographic device, lateral radiographs, cardiological and odontological examinations, and quality of life measures prior to and following intervention with an custom-made MAD. At the short-term follow-up 4-6 weeks after habituation with the MAD, the severity of SDB according to the apnoea-hypopnoea index had decreased from 25.1 +/- 9.4 (mean +/- SD) to 14.7 +/- 9.7 (p = 0.003). An increase in the inferior region of the PAW (7 +/- 5 mm) was observed on radiographs (p = 0.0001). However, no correlation between the effect of the MAD on the dimensions of the PAW and its effect on SDB was found. At the 6-month follow-up, the sleep apnoea-related symptoms had decreased by 31% (p = 0.003). Quality of life remained stable. BNP were reduced from 195.8 +/- 180.5 pg/ml to 148.1 +/- 139.9 pg/ml (p = 0.035). LVEF, however, remained unchanged. At the 12-month follow-up, 64 % of the patients were still using the MAD. Three patients withdrew from the study because of discomfort with the MAD. In most patients, MAD treatment had no severe side effect on the signs or symptoms of temporomandibular disorders. However, dental complications were observed. In conclusion, in patients with stable CHF who are experiencing problems with SDB, MAD intervention appears to reduce the severity of SDB, sleep apnoea-related symptoms, and neurohormonal activity. A lower tendency for PAW collapse may explain the effect observed on SDB. The reduction in plasma BNP may indicate decreased cardiac strain as a result of treatment of SDB. The 5-year survival rate, measured from the start of MAD intervention, was higher in the group that used a MAD than in the group that did not use a MAD (p = 0.036). No severe side effects on the stomatognathic system were observed during the intervention, and most patients--edentulous included--tolerated the treatment well. Impaired oral health, including reduced dentition and edentulousness, seemed to limit the use of the MAD in this group of elderly patients, both because of technical difficulties and because of the increased risk of dental complications. However, because the treatment of SDB is important in the management of CHF, the MAD intervention seems to be a valuable method in the treatment arsenal of SDB.     

Use of a mandibular advancement device in obstructive sleep apnoea

The present study investigated the effectiveness of an intra-oral mandibular advancement device in the treatment of patients with obstructive sleep apnoea (OSA) who could not tolerate or who had failed to comply with continuous positive airway pressure (CPAP). Thirty-five patients diagnosed by sleep study as suffering from OSA, who had either been unable to tolerate or had been non-compliant with CPAP treatment, were included in the study. The subjects completed an Epworth sleep questionnaire. The subjects then had an oral appliance made. After using the appliance for 3 months, the patients repeated the questionnaires and had a repeat sleep study performed with the oral appliance in situ. Thirty-one subjects completed the investigation. Mean AHI pre- and post-study were 26.64 and 24.06, respectively (P > 0.05). Mean Epworth scores pre- and post-study were 16.32 and 14.64, respectively (P > 0.05). Those patients with a pre-study AHI < 20 (n = 23), however, did significantly better with the appliance (P < 0.0001). Those patients with a pre-study AHI > 20 did not benefit from this device (P > 0.05). The main problems encountered were initial jaw discomfort in 18 patients and dry mouth in 11 patients (both of which improved with continued usage). It was concluded that the type of appliance used in this study can be recommended for those with mild OSA who are unable to tolerate CPAP.     

An investigation into the changes in airway dimension and the efficacy of mandibular advancement appliances in subjects with obstructive sleep apnoea.

This prospective clinical study evaluates a group of 37 male Caucasians with obstructive sleep apnoea for changes in airway dimension and the efficacy associated with the use of mandibular advancement splints. Lateral skull radiographs were obtained with the subjects--upright in occlusion, supine in occlusion, and supine in protrusion. Each radiograph was traced and digitized, and changes in mandibular position, airway dimensions, and hyoid were examined. Subjects were invited to complete pre- and post-treatment questionnaires, and interviewed following fitting of a removable Herbst mandibular advancement splint. Significant changes were recorded in the airway dimensions in response to both a change in position, from upright to supine, and in response to mandibular advancement. A compliance rate of 76 per cent was achieved with no reported serious complications associated with the use of mandibular advancement devices.     

Short-term effects of a mandibular advancement device on obstructive sleep apnoea: an open-label pilot trial

Obstructive sleep apnoea (OSA) is a common sleep disorder, which is, among others, associated with snoring. OSA has a considerable impact on a patient's general health and daily life. Nasal continuous positive airway pressure (nCPAP) is frequently used as a "gold standard" treatment for OSA. As an alternative, especially for mild/moderate cases, mandibular advancement devices (MADs) are prescribed increasingly. Their efficacy and effectiveness seem to be acceptable. Although some randomized clinical trials (RCTs) have been published recently, most studies so far are case studies. Therefore, our department is planning a controlled RCT, in which MADs are compared with both nCPAP and a control condition in a parallel design. As a first step, an adjustable MAD was developed with a small, more or less constant vertical dimension at different mandibular positions. To test the device and the experimental procedures, a pilot trial was performed with 10 OSA patients (six mild, four moderate; one women, nine men; mean age = 47.9 +/- 9.7 years). They all underwent a polysomnographic recording before as well as 2-14 weeks after insertion of the MAD (adjusted at 50% of the maximal protrusion). The apnoea-hypopnoea index (AHI) was significantly reduced with the MAD in situ (P = 0.017). When analysed as separate groups, the moderate cases showed a significantly larger decrease in AHI than the mild cases (P = 0.012). It was therefore concluded from this pilot study that this MAD might be an effective tool in the treatment of, especially, moderate OSA.     

Long‐term side effects on the temporomandibular joints and oro‐facial function in patients with obstructive sleep apnoea treated with a mandibular advancement device

Patients with obstructive sleep apnoea (OSA) in long‐term treatment with a mandibular advancement device (MAD) to increase the upper airway space may develop changes in the temporomandibular joint (TMJ) and the oro‐facial function due to the protruded jaw position during sleep. The aim was to investigate the influence of long‐term MAD treatment on the TMJs, oro‐facial function and occlusion. This prospective study included 30 men and 13 women (median age 54) with OSA [Apnoea–Hypopnoea Index (AHI): 7–57]. They were examined with the Nordic Orofacial Test Screening (NOT‐S), the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and cone beam computed tomography (CBCT) of the TMJs. The examination was performed before MAD treatment (T0), and 3–6 months (T1, no CBCT), 1 year (T2) and 3 years (T3) after treatment start. The results were analysed as long term (T0–T3, n = 14) and short term (T0–T2, n = 24) by t‐test, Fisher's exact test and anova . Both long‐ and short‐term analyses revealed a reduction in AHI (P < 0·002). Significant long term were increased scores in the NOT‐S Interview (P < 0·045), reduced vertical overbite (P < 0·031) and increased jaw protrusive movement (P < 0·027). TMJ changes were found as joint sounds in terms of reciprocal clicking and crepitus, short term as a decrease and subsequent recurrence (P < 0·053; P < 0·037). No significant radiological changes were found. In conclusion, MAD treatment is beneficial to some OSA patients, but might induce changes in the TMJs, the oro‐facial function and the occlusion. However, these changes seemed to be less harmful than previously reported with careful adaptation, control and follow‐ups.     

Volumetric three-dimensional computed tomographic evaluation of the upper airway in patients with obstructive sleep apnoea syndrome treated by maxillomandibular advancement

Obstructive sleep apnoea syndrome is the periodic reduction or cessation of airflow during sleep together with daytime sleepiness. Its diagnosis requires polysomnographic evidence of 5 or more episodes of apnoea or hypopnoea/hour of sleep (apnoea/hypopnoea index, AHI). Volumetric 3-dimensional computed tomographic (CT) reconstruction enables the accurate measurement of the volume of the airway. Nasal continuous positive airway pressure (CPAP) is the conventional non-surgical treatment for patients with severe disease. Operations on the soft tissues that are currently available give success rates of only 40%-60%. Maxillomandibular advancement is currently the most effective craniofacial surgical technique for the treatment of obstructive sleep apnoea in adults. However, the appropriate distance for advancement has not been established. Expansion of the air-flow column volume did not result in an additional reduction in AHI, which raises the important issue of how much the maxillomandibular complex should be advanced to obtain an adequate reduction in AHI while avoiding the risks of overexpansion or underexpansion. We have shown that there is a significant linear relation between increased absolute upper airway volume after advancement and improvement in the AHI (p=0.013). However, increases in upper airway volume of 70% or more achieved no further reduction in the AHI, which suggests that the clinical improvement in AHI reaches a plateau, and renders further expansion unnecessary. This gives a new perspective to treatment based on the prediction of changes in volume, so the amount of sagittal advancement can be tailored in each case, which replaces the current standard of 1 cm.     

Current principles in the management of obstructive sleep apnoea with mandibular advancement appliances.

This paper looks at the role of mandibular advancement splints in the management of obstructive sleep apnoea, as part of a multidisciplinary approach. Clinical guidance is provided on the rationale for use, patient selection, design features and the associated risk to benefit ratio.     

Effect of mandibular advancement device on sleep bruxism score and sleep quality

Statement of problem

The use of mandibular advancement devices (MADs) in the treatment of sleep bruxism is gaining widespread importance. However, the effects of MADs on sleep bruxism scores, sleep quality, and occlusal force are not clear.

Effects of orthognathic surgery on pharyngeal airway and respiratory function during sleep in patients with mandibular prognathism

The aim of this study was to determine changes in overnight respiratory function and craniofacial and pharyngeal airway morphology following orthognathic surgery. The subjects were 40 patients in whom mandibular prognathism was corrected by orthognathic surgery: a one-jaw operation in 22 patients and a two-jaw operation in 18 patients. Morphological changes were studied using cone beam computed tomography immediately before surgery and at more than 6 months after surgery, and the apnoea–hypopnoea index (AHI) was measured with a portable polysomnography system. Pharyngeal airway volume was decreased significantly after surgery, especially in the one-jaw operation group. AHI was not changed significantly after surgery in either group, although AHI in one patient in the one-jaw operation group was increased to 19 events/h. There was no significant change in pharyngeal airway morphology in that patient, but he was obesity class 1 and was 54 years old. In conclusion, some patients who are obese, have a large amount of mandibular setback, and/or are of relatively advanced age may develop sleep-disordered breathing after mandibular setback; a two-jaw operation should therefore be considered in skeletal class III patients who have such risks because it decreases the amount of pharyngeal airway space reduction caused by mandibular setback surgery.     

The use of videofluoroscopy in the assessment of the pharyngeal airway in obstructive sleep apnoea

This prospective cohort study evaluated the use of videofluoroscopy in assessing changes in both antero-posterior (A-P) and transverse pharyngeal airway dimensions in patients with obstructive sleep apnoea (OSA). Forty patients [32 males and 8 females; mean age of 49.3 (SD = 10.79) years] with confirmed OSA, referred for mandibular advancement appliance (MAA) therapy were recruited. Patients received a customized Herbst MAA, adjusted for maximum comfortable protrusion. A standard lateral cephalogram, supine A-P, and transverse videofluoroscopic investigations were performed. Repeat supine videofluoroscopic investigations were undertaken with the MAA in situ. Parametric tests were used to evaluate the study hypotheses as the data were normally distributed. A paired t-test was employed to determine both the impact of posture on the airway using upright cephalometry and supine videofluoroscopy and the effect of MAA insertion on A-P and transverse pharyngeal airway dimensions. Following a change in posture from upright to supine, highly statistically significant (P < 0.001) changes were observed for all lateral pharyngeal dimensions. Statistically significant increases in minimum lingual airway (P < 0.001) and maximum transverse pharyngeal airway (P < 0.001) were found following MAA insertion. A reduction in soft palate area (P = 0.029) and pharyngeal height (P < 0.001) was also noted. Videofluoroscopy offers a useful dynamic assessment of the pharyngeal airway in both the A-P and transverse planes in patients with OSA.     

Maxillary, mandibular and chin advancement surgery for the treatment of obstructive sleep apnoea

The aim of this retrospective study was to determine the effectiveness of maxillary, mandibular and chin advancement (MMCA) surgery as a treatment for obstructive sleep apnoea and to determine the cephalometric parameters of this surgery. Twenty consecutive adult patients with obstructive sleep apnoea for whom other treatments (constant positive airway pressure, mandibular advancement splint and soft tissue surgery) had failed underwent MMCA surgery. Pre- and post-surgical polysomnography studies measuring the Respiratory Disturbance Index (RDI), minimum blood oxygen saturation (MinSaO2) and Epworth Sleepiness Scale (ESS) were compared. Lateral cephalometric radiographs measuring the pre- and post-surgical posterior airway space (PAS) were also analysed. Regression analysis indicated that the change in PAS at the level of B point largely accounted for the change in the RDI, although it was not significantly related with the postoperative oxygen saturation. MMCA surgery was found to be effective as a treatment for obstructive sleep apnoea, and improved all postoperative measures in this study. There was a significant relationship between B point, the PAS and a reduction in RDI.     

双侧拉杆式口腔矫治器治疗OSAHS前后上气道容积变化及相关因素分析

目的 通过计算机体层摄影观察轻、中度阻塞型睡眠呼吸暂停、低通气综合征患者戴用双侧拉杆式口腔矫治器前后上气道形态变化及其相关因素分析.方法 经夜间多导睡眠仪监测确诊为OSAHS的男性患者9名,年龄25～43岁,平均37岁（中位数）,戴用口腔矫治器治疗有效.3个月后分别行CT扫描,三维重建后行定量分析.结果 所有患者戴用矫治器后上气道各段容积及总容积均增大.总容积的增加百分比与患者体重指数成负相关（r=-0.70,P=0.03）,与患者下颌平面角（MP-SN）没有显著相关性（r=-0.43,P=0.25）.上气道容积的增加与患者睡眠呼吸障碍的严重程度及改善程度无明显相关关系（r=0.30,P=0.43;r=0.39,P=0.29）.结论 双侧拉杆式口腔矫治器使OSAHS患者上气道大小、形态趋于正常.体重指数影响气道大小改善的程度.同时气道大小改善的程度与患者的睡眠呼吸状况改善并不一致.     

双侧拉杆式口腔矫治器治疗OSAHS前后上气道容积变化及相关因素分析

Objective To investigate the morphologic change of upper airway induced by oral appliance(OA) of double-pull rods in obstructive sleep apnea and hypopnea syndrome(OSAHS) and analyze relevant factors, subsequently investigate treatment mechanism of OA for OSAHS. Methods Nine OSAHS patients (male, 25-43yeas old), diagnosed by polysomnography, successfully treated with OA. After 3 months treatment, each patient received Helical computed tomography in central relation with and without OA respectively. Upper airway structures were reconstructed at threedimension and measured by VG Studio. Results The volume of the upper airway of all 9 patients were increased when patients with OA. A significant negative relationship was found between △volume and BMI(r=-0. 70,P=0. 03). No significant relationship is found between△volume and FH-MP(r=-0. 43,P=0. 25), between△volume and AHI (without OAs)(r=0. 30,P=0. 43), and between△volume and△AHI(r= 0. 39, P=0. 29). Conclusions OSAHS patients can be effectively treated with mandibular advancement devices (MAD), with increased volume of upper airway which is influenced by BMI. The degree of volume increase is not consistent with improvement induced by treatment in patients with OSAHS.