Mandibular Advancement Splint Treatment Research Articles

Effect of mandibular advancement splint therapy on cardiac autonomic function in obstructive sleep apnoea.

This study aimed to evaluate the effect of mandibular advancement splint (MAS) therapy on cardiac autonomic function in patients with obstructive sleep apnoea (OSA) using heart rate variability (HRV) analysis. Electrocardiograms (ECG) derived from polysomnograms (PSG) of three prospective studies were used to study HRV of patients with OSA before and after MAS treatment. HRV parameters were averaged across the entire ECG signal during N2 sleep using 2-min epochs shifted by 30s. Paired t-tests were used to compare PSG and HRV measures before and after treatment, and the percent change in HRV measures was regressed on the percent change in apnoea-hypopnea index (AHI). In 101 patients with OSA, 72% were Caucasian, 54% men, the mean age was 56±11 years, BMI 29.8±5.3 kg/m2, and treatment duration was 4.0±3.2 months. After MAS therapy, there was a significant reduction in OSA severity (AHI, - 18 ± 16 events per hour, p < 0.001) and trends towards increased low-frequency to high-frequency ratio, low-frequency power, and reduced high-frequency power (LF:HF, - 0.4 ± 1.5, p = 0.01; LF, - 3 ± 16 nu, p = 0.02, HF, 3.5 ± 13.7 nu, p = 0.01). Change in NN intervals correlated with the change in AHI (β(SE) = - 2.21 (0.01), t = - 2.85, p = 0.005). No significant changes were observed in the time-domain HRV markers with MAS treatment. The study findings suggestthat successful MAS treatment correlates with changes in HRV, specifically the lengthening of NN intervals, a marker for improved cardiac autonomic adaptability.

Friedman Score in Relation to Compliance and Treatment Response in Nonsevere Obstructive Sleep Apnea.

Nonsevere obstructive sleep apnea (OSA) is most often treated with a continuous positive airway pressure (CPAP) device or a mandibular advancement splint (MAS). However, patient compliance with these treatments is difficult to predict. Improvement in apnea-hypopnea index (AHI) is also somewhat unpredictable in MAS treatment. In this study, we investigated the association between Friedman tongue position score (Friedman score) and both treatment compliance and AHI improvement in patients with nonsevere OSA receiving CPAP or MAS treatment. 104 patients with nonsevere OSA were randomly allocated to CPAP or MAS treatment and followed for 12 months. Data were collected through a medical examination, questionnaires, sleep recordings from ambulatory type 3 polygraphic sleep recording devices, and CPAP recordings. Associations between Friedman score, treatment compliance, and AHI improvement were analysed with logistic regression analyses. Friedman score was not associated with treatment compliance (odds ratio [OR]: 0.85, 95% confidence interval [CI]: 0.59–1.23), or AHI improvement (OR: 1.05, 95% CI: 0.62–1.76) in the overall study sample, the CPAP treatment group, or the MAS treatment group. Adjustment for socioeconomic factors, body mass index, and tonsil size did not significantly impact the results. Although Friedman score may predict OSA severity and contribute to the prediction of success in uvulopalatopharyngoplasty, we found no association between Friedman score and treatment compliance in patients with nonsevere OSA receiving CPAP or MAS treatment, nor did we find any association between Friedman score and AHI improvement. Factors other than Friedman score should be considered when deciding whether a patient with nonsevere OSA should be treated with CPAP or MAS.

Changes in sleep and airway variables in patients with obstructive sleep apnea after mandibular advancement splint treatment.

Obstructive sleep apnea (OSA) is an extensive public health problem that imposes considerable morbidity. Mandibular advancement splint (MAS) therapy is a well tolerated treatment, but success rates are difficult to predict. Our objective was to investigate the relationship of oropharyngeal airway dimensions, sleep characteristics, patient biometrics, and treatment response within an OSA patient sample. Records of 33 adults were assessed retrospectively with the use of Dolphin 3D and Image J to measure the airway on pretreatment supine cone-beam computed tomography images and derived lateral cephalograms. The patients used Somnodent (Somnomed; Crows Nest, Australia) MAS appliances, which were titrated over 6-8weeks. Appliance titration measurements and pre- and posttreatment polysomnograms were assessed. Respiratory disturbance index (RDI), absolute and percentage changes in RDI, non-rapid eye movement (NREM) RDI, rapid eye movement (REM) RDI, supine and nonsupine NREM and REM RDI, and minimal blood-oxygen saturation variables were evaluated. The associations of measurements from 2D and 3D minimal anterior-posterior linear distance and 3D airway variables with MAS treatment response were estimated. Combined effects of baseline total airway volume, body mass index, neck circumference, location of minimal cross sectional area, and OSA severity were associated with treatment response. Patients with higher initial OSA and more superiorly located airway constriction showed enhanced treatment response to MAS therapy. Airway constriction due to maxillofacial disproportions rather than soft tissue obstruction also showed better treatment response. No significant relationships were found in lateral cephalogram measurements.

Differences in three-dimensional craniofacial anatomy between responders and non-responders to mandibular advancement splint treatment in obstructive sleep apnoea patients.

The primary aim of this study was to assess the differences in the upper airway morphology between responders and non-responders to mandibular advancement splint (MAS) treatment in obstructive sleep apnoea (OSA) management. The secondary aim was to assess the correlation between the minimum cross-sectional area of the upper airway and the anatomical structures (i.e. mandibular external length, maxillary length, soft palate length, area of the tongue, maxillomandibular enclosure size, and anatomical balance ratio) surrounding the upper airway. The third aim was to assess the differences in the overall skeletal configuration between responders and non-responders to MAS treatment. Data from 64 patients (23 females and 41 males) diagnosed with OSA by polysomnography (PSG) at baseline and provided with an adjustable MAS were analysed. All patients had NewTom3G cone beam computed tomography (CBCT) scans, performed in the supine position, at baseline. After acclimatization to MAS, follow-up PSG tests were performed to assess the apnoea-hypopnea index (AHI) with the MAS in situ. Responders were defined by a post-treatment AHI less than 10/hour and at least 50 per cent reduction in AHI, and non-responders by a post-treatment AHI at least 10/hour or less than 50 per cent reduction in AHI. Several upper airway and anatomical variables surrounding the upper airway based on CBCT images were measured to determine the differences between responders and non-responders to MAS. There were 36 responders (AHI = 24.8 ± 11.9 at baseline) and 28 non-responders (AHI = 31.2 ± 20.3 at baseline) to MAS. There were no significant differences in the upper airway morphology between responders and non-responders (P = 0.17-0.93) or in the anatomical structure surrounding the upper airway (P = 0.24-0.58). Within the limitations of this study, it can be concluded that there are no significant differences in upper airway morphology and in anatomical structures surrounding the upper airway between responders and non-responders to MAS treatment. These findings suggest that the craniofacial anatomical structures analyzed in this study cannot explain the response to MAS treatment.

Prediction of MAS Therapy Response in Obstructive Sleep Apnoea Patients using Clinical Data.

Mandibular Advancement Splint (MAS) is an oral appliance based treatment to Obstructive Sleep Apnoea (OSA) patients that is only effective for some patients. We present an investigation to predict MAS treatment response in OSA patients. A unique dataset in a large number (n=543 patients) consisting of convenient measurement such as demographic, anthropometric and Polysomnography (PSG) variables was utilised. Treatment Responders were defined as those with ≥50% reduction in Apnoea Hypopnoea Index (AHI) resulting in an AHI of less than 10 after the treatment process. Leaveone-out cross validation results using a Quadratic Neural Network showed an overall accuracy of 63%, with 63% sensitivity and 63% specificity for correctly predicting treatment response which is an improvement on previously published results.

Differences in three-dimensional craniofacial anatomy between responders and non-responders to mandibular advancement splint treatment in obstructive sleep apnea patients

Differences in three-dimensional craniofacial anatomy between responders and non-responders to mandibular advancement splint treatment in obstructive sleep apnea patients

Effect of mandibular advancement splint treatment on tongue shape in obstructive sleep apnea.

Mandibular advancement splints (MAS) can effectively treat obstructive sleep apnea (OSA); however, treatment response is variable, and the mechanisms behind differences in treatment outcomes are still not well understood. The aims of this study were (1) to assess the effects of MAS on tongue shape and (2) to compare tongue shape changes with MAS between treatment responders and nonresponders. Sixty-eight adults with symptomatic mild to severe OSA were included. A custom-made MAS was provided to patients, and treatment outcome was determined by polysomnography. Two-dimensional tongue measurements were evaluated using sagittal and axial MRI image slices without and with MAS in situ. Tongue measurements of height, length, width, area, and shape (height/length) were collected. Additional measurements of surrounding upper airway structures, soft palate length width and area and upper airway area, length and minimum width were measured on sagittal image slices. Based on polysomnography with MAS in situ, 47 patients were classified as responders (≥50% reduction in apnea-hypopnea index [AHI] from baseline), and 21 were nonresponders (<50% AHI reduction). There was no change in sagittal tongue area with insertion of MAS, although there was a change in most of parameters of tongue shape. Responders showed a greater decrease in tongue length with MAS in situ compared to nonresponders (-0.64 ± 0.46 vs -0.32 ± 0.51 cm, p = 0.016). This study reports a detailed two-dimensional analysis of tongue dimensions as well as assessment of adjacentsoft palate shape and upper airway structures without and with MAS treatment for OSA. Our finding suggests that MAS does induce changes in tongue shape. MAS treatment responders showed a greater decrease in tongue length (between the tongue tip and hyoid bone) with MAS in situ; whether differences in alteration of tongue position with MAS explain differences in treatment response requires further investigation.

Patient's experience of treatment for sleep apnoea with a mandibular advancement splint

Background and aimsObstructive sleep apnoea (OSA) is a well recognised clinical disorder in which there is narrowing and repeated collapse of the upper airway during sleep resulting in the cessation of breathing. Patients with mild to moderate sleep apnoea are often provided with mandibular advancement splint (MAS) therapy as a form of first line or definitive treatment. The aims of this audit were to evaluate patient satisfaction and success of MAS therapy. Methods93 patients diagnosed with sleep apnoea and suitable for a splint were recruited prospectively at Queen Victoria Hospital, East Grinstead between January 2009 and October 2010. A patient satisfaction questionnaire was developed by health professionals involved in the care of patients with sleep apnoea and assessed for face and content validity and reliability. Participants completed the questionnaire six weeks after the splint was fitted. Results44% who previously experienced snoring now reported no snoring and 47% reported less snoring since wearing the MAS appliance. 69% reported complete resolution of sleep apnoea symptoms. 37% experienced aching teeth and 33% experienced having a dry throat when wearing the appliance. 86% of sleeping partners felt that their quality of sleep was improved following their partners treatment. ConclusionsThe standards set for each criteria in this audit were met. MAS treatment has a key role to play in the management of obstructive sleep apnoea with high rates of patient satisfaction and the majority of patients partners reporting a significant improvement in their own and their partners sleep quality.

Association between resting jaw muscle electromyographic activity and mandibular advancement splint outcome in patients with obstructive sleep apnea

The muscles of mastication are important in positioning the mandible and can therefore affect the patency of the upper airway. The aim of this study was to determine whether resting masticatory muscle activity influences the response to mandibular advancement splint treatment in patients with obstructive sleep apnea. Thirty-eight adult patients with obstructive sleep apnea were recruited for the study. Baseline electromyographic activities of the right anterior and posterior temporalis, masseter, and submandibular muscles were recorded with surface electrodes while the patients were awake, in the upright and supine positions, with the jaw in the postural position, and with and without a mandibular advancement splint. Muscle activity of the patients with obstructive sleep apnea was compared between responders (apnea-hypopnea index change ≥50%, and <10 events per hour) and nonresponders (apnea-hypopnea index change <50%) to mandibular advancement splint treatment. There were 18 responders and 20 nonresponders to mandibular advancement splint treatment. The responders had a trend for increased muscle activity in all muscle groups and scenarios. The resting muscle activity of the submandibular and masseter muscles while lying at rest and of the submandibular and posterior temporalis muscles while lying with the mandibular advancement splint in place were significantly greater (P <0.05) in the responders than in the nonresponders. Inherent baseline differences in muscle activity between responders and nonresponders to mandibular advancement splint treatment in adults with obstructive sleep apnea were observed. This preliminary study suggests that there might be a correlation between responsiveness with mandibular advancement splint treatment and baseline muscle activity.

Influence of Oral and Craniofacial Dimensions on Mandibular Advancement Splint Treatment Outcome in Patients With Obstructive Sleep Apnea

Mandibular advancement splints (MASs) can effectively treat obstructive sleep apnea (OSA); however, no validated and reliable prediction method for treatment outcome currently exists. The efficacy of MAS may relate to anatomic factors, including craniofacial size and upper-airway soft-tissue volume and anatomic balance between them. We aimed to assess whether craniofacial and oral measurements are associated with MAS treatment outcome. Dental impressions and lateral cephalometric radiographs were obtained from patients with OSA prior to commencing MAS treatment. Intertooth distances and palatal depths were measured on dental casts, and standard cephalometric analysis was performed with the addition of cross-sectional area (CSA) of the tongue and bony oral enclosure. Treatment outcome was determined by polysomnography. Of 53 patients, 25 were complete responders (posttreatment apnea-hypopnea index [AHI] < 5/h), 17 were partial responders (≥ 50% AHI reduction), and 11 were nonresponders (< 50% AHI reduction). Cephalometric analyses did not reveal any significant differences between responders and nonresponders. Oral cavity measurements or CSA did not differ with treatment outcome; however, there was a trend toward a larger tongue CSA in complete vs partial and nonresponders (39.5 ± 1.3 cm(2) vs 35.5 ± 0.5 cm(2), P = .09). Tongue/oral enclosure CSA ratio, indicating a larger tongue for a given oral cavity size, was greater in complete responders (P = .012, n = 30). Oral dimensions do not appear to differ between patients who respond and those who do not respond to MAS treatment. However, the larger tongue for a given oral cavity size in responders suggests that MAS may help to correct anatomic imbalance. Further research to assess whether the ratio between tongue and bony oral enclosure size may be useful in selecting patients for MAS treatment is warranted.