Oral Appliances for the Management of OSA: An Updated Review of the Literature

Effects of mandibular advancement devices on the evolution of obstructive sleep apnea

PURPOSE

Mandibular advancement devices (MADs) are a treatment for obstructive sleep apnea (OSA). Titration is a necessary component of proper fitting of MADs, yet little is known about what happens at each step of the titration. The objectives of this study were to determine the clinical and paraclinical evolution of OSA at every mm of MAD advancement.

METHODS

Volunteers were fitted with MADs set to 50% of maximum advancement. MAD clinical and paraclinical results were recorded at every additional mm-titration, including apnea-hypopnea index (AHI), as well as symptoms of sleepiness and fatigue.

RESULTS

In 20 volunteers with OSA, the MAD had a significant effect on every polygraphic parameter at the onset of use. The mean AHI with MAD fell by 15.2/h (p < 0.001). The mean Epworth Sleepiness Score and Pichot Fatigue questionnaire with MAD fell by 2.0 (p = 0.0687) and 2.4 (p = 0.1073) respectively. There was no proportionality between clinical gains (drowsiness and fatigue) and AHI improvements.

CONCLUSIONS

MADs led to a significant improvement in AHI and other polygraphic parameters from the onset of use. The decrease of clinical symptoms (drowsiness and fatigue) was more complex to interpret because of the small decreases observed. The absence of concordance between AHI improvement and clinical symptoms was nevertheless objectively quantified and symptoms were alleviated with advancements. The findings suggest that it may be appropriate to use clinical symptoms as a main aim of titration, since the improvement in AHI is reached at the onset of MAD use.

Concurrent laparoscopic sleeve gastrectomy with uvulopalatopharyngoplasty in the treatment of morbid obesity comorbid with severe obstructive sleep apnea: a retrospective cohort study

STUDY OBJECTIVES

This study aimed to evaluate the safety and short-term effect of contemporaneous surgeries (bariatric surgery plus uvulopalatopharyngoplasty [UPPP]) in the treatment of morbid obesity comorbid with severe obstructive sleep apnea (OSA).

METHODS

A retrospective cohort study was performed to identify patients with obesity and severe OSA who underwent laparoscopic sleeve gastrectomy (LSG) with or without UPPP surgeries between December 2019 and December 2021 in our center. Patients were divided into 2 groups according to different surgical methods (contemporaneous group [LSG with UPPP] vs LSG-only group). Data about surgical safety, OSA remission, and effectiveness of weight loss were collected and analyzed between the 2 groups before and 12 months after surgery.

RESULTS

A total of 101 patients were included in this study (contemporaneous group [LSG with UPPP], n = 42 vs LSG only group, n = 59). There was no significant difference in surgical safety between the 2 groups, and both OSA and obesity were significantly improved at 12.5 ± 2.1 months postoperative follow-up. The apnea-hypopnea index decreased from 68.7 ± 30.4 events/h to 10.2 ± 7.0 events/h in the contemporaneous group (P < .001) and from 64.7 ± 26.2 events/h to 18.9 ± 9.8 events/h in the LSG group (P < .001). Moreover, the apnea-hypopnea index decreased to below 5 events/h in 50% of patients (21/42) in the contemporaneous group but only in 13.5% of patients in the LSG group (P < .001). In the LSG group 20 (34%) patients achieved a reduction in apnea-hypopnea index < 15 events/h and resolution of daytime sleepiness.

CONCLUSIONS

Contemporaneous surgery (concurrent bariatric and UPPP surgeries) is feasible and an effective option for patients with obesity and severe OSA. However, our finding suggests that approximately a third of patients undergoing LSG with UPPP may not derive significant benefit from the UPPP portion of the contemporaneous surgical approach.

CITATION

Yang C, Yu W, Yao K, et al. Concurrent laparoscopic sleeve gastrectomy with uvulopalatopharyngoplasty in the treatment of morbid obesity comorbid with severe obstructive sleep apnea: a retrospective cohort study. J Clin Sleep Med. 2024;20(4):555-564.

Does oral appliance efficacy in treating obstructive sleep apnea depend on the appliance specialist's experience?

PURPOSE

In France, oral appliances (OAs) are the first-line treatment for moderate and second-line treatment for severe obstructive sleep apnea-hypopnea syndrome. In general, the sleep specialist refers his/her patient to the appliance specialist for the impressions and the fitting. However, is there a relationship between the volume of activity of the appliance specialist and the efficacy of this device?

METHODS

Our unit includes seven appliance otolaryngology specialists whose activities are highly variable (number of patients varying by a factor of almost 10). Data from a prospective follow-up registry of patients treated with an OA for moderate and severe obstructive sleep apnea-hypopnea syndrome were studied, and differences in outcomes between practitioners in the team were sought.

RESULTS

Among 859 patients, OAs significantly reduced the apnea-hypopnea index. Even if the patients were not completely comparable from one practitioner to another, there was a significant heterogeneity in efficacy (complete or partial response of the apnea-hypopnea index and failure of OAs) between practitioners (p = 0.0038; 0.0011; 0.0007 respectively), with better results in practitioners with a higher level of OA activity.

CONCLUSION

The findings suggest that it may be preferable to refer patients to OA practitioners who see a higher volume of patients with moderate or severe obstructive sleep apnea-hypopnea syndrome treated with an OA.

A Concise Review of Polysomnography and Obstructive Sleep Apnea for the Neurophysiologist

SUMMARY

Sleep as an electrical phenomenon in the brain was first recorded in 1875. Over the next 100 years, recordings of sleep evolved into modern-day polysomnography, which includes not only electroencephalography but also combinations of electro-oculography, electromyography, nasal pressure transducers, oronasal airflow monitors, thermistors, respiratory inductance plethysmography, and oximetry. The most common usage of polysomnography is to identify obstructive sleep apnea (OSA). Research has demonstrated that subjects with OSA have distinctive patterns detected by EEG. The evidence indicates that increased slow activity is seen in both sleep and wake for subjects with OSA and that these changes are reversible with treatment. This article reviews normal sleep, changes in sleep that result from OSA, and the effect that treatment of OSA via continuous positive airway pressure therapy has on normalizing the EEG. A review of alternative OSA treatment options is included, although their effects on EEG in OSA patients have not been studied.

Dental and Occlusal Changes during Mandibular Advancement Device Therapy in Japanese Patients with Obstructive Sleep Apnea: Four Years Follow-Up

Dentoskeletal changes caused by the long-term use of mandibular advancement devices (MADs) for obstructive sleep apnea (OSA) have rarely been investigated in Japan. We assessed the long-term dentofacial morphological changes in 15 Japanese patients with OSA who used two-piece MADs for an average of 4 years. Lateral cephalography analyses were performed initially and 4 years later (T1). The dental assessment included overjet, overbite, upper anterior facial height, lower anterior facial height (LAFH), total anterior facial height (TAFH), and anterior facial height ratio. Dental casts were digitized and analyzed using a 3D scanner. Changes in the apnea hypopnea index (AHI) and other sleep-assessment indices were assessed using polysomnography and out-of-center sleep testing. Radiography revealed lingual inclination of the maxillary central incisors, labial inclination of the mandibular central incisors, clockwise rotation of the mandible, and an increase in the TAFH and LAFH at T1. In the dental cast analysis, the diameter width and palatal depth tended to decrease and increase, respectively. There was a significant decrease in the AHI and other sleep assessment indices after using the MADs for approximately 4 years. However, these findings do not provide a strong basis and should be interpreted cautiously. Future studies should have a larger sample size and should further investigate the long-term occlusal and dental changes caused by the original MADs in Japanese patients with OSA.

Optimizing Mandibular Advancement Maneuvers during Sleep Endoscopy with a Titratable Positioner: DISE-SAM Protocol

Mandibular advancement devices (MAD) are an effective alternative treatment to CPAP. Different maneuvers were performed during drug sleep-induced endoscopy (DISE) to mimic the effect of MAD. Using the Selector Avance Mandibular (SAM) device, we aimed to identify MAD candidates during DISE using a titratable, reproducible, and measurable maneuver. This DISE-SAM protocol may help to find the relationship between the severity of the respiratory disorder and the degree of response and determine the advancement required to improve the collapsibility of the upper airway. Explorations were performed in 161 patients (132 males; 29 females) with a mean age of 46.81 (SD = 11.42) years, BMI of 27.90 (SD = 4.19) kg/m², and a mean AHI of 26.51 (SD = 21.23). The results showed no relationship between severity and MAD recommendation. Furthermore, there was a weak positive relationship between the advancement required to obtain a response and the disease severity. Using the DISE-SAM protocol, the response and the range of mandibular protrusion were assessed, avoiding the interexaminer bias of the jaw thrust maneuver. We suggest prescribing MAD as a single, alternative, or multiple treatment approaches following the SAM recommendations in a personalized design.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared in order to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Because sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep-disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Since sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

[Mandibular advancement device and multidisciplinary consultation of sleep-disorders]

BACKGROUND

Multidisciplinary consultation of sleep-disorders can include recommendation of a mandibular advancement device (MAD) for some patients with obstructive sleep apnea syndrome (OSAS).

AIM

To assess the outcomes of patients for whom an oral MAD was prescribed following multidisciplinary consultation for OSAS in a University Hospital Center.

METHODS

All patients referred by hospital or community specialist who had visited this specialized service from December 2015 to December 2017 and to whom an MAD was prescribed were included in this study. The objective was to analyze their clinical course after this consultation and to assess the effectiveness of these devices in this population.

RESULTS

In all, 184 patients were seen by the multidisciplinary consultation between December 2015 and December 2017. An MAD was offered to 148 patients and 70 of these went on to have one. Of these 52 of them received follow-up polygraphy (PG) with it in place. This confirmed effectiveness in 18 cases (decrease of at least 50% of the AHI. The average AHI went from 34.8/hr to 22.5/hr. Sixty-five of the 148 patients were lost to follow-up.

CONCLUSION

After specialized consultation on sleep-disorders, only one-third of the patients to whom an OA was prescribed had polygraphic exam. OA was less effective than in equivalent series. Correctives measures (such as a multidisciplinary standard sheet) have been set up to ensure a close follow-up of patients.

Gradual reduction in the STOP score in patients with obstructive sleep apnea undergoing oral appliance therapy

Purpose In the treatment of obstructive sleep apnea (OSA), there is not yet a convenient tool for deciding whether a mandibular advancement oral appliance (OA) is adequately adjusted or when to perform post-treatment sleep-testing. We hypothesized that a gradual reduction in the STOP (snoring, tiredness during daytime, observed apnea, high blood pressure) score, i.e., fewer Yes responses in the STOP questionnaire, in patients undergoing OA treatment could be an indicator of better OA adjustment and, thus, the best timing for follow-up polysomnography.Methods The STOP score was recorded at every patient visit when the OA was adjusted ventrally as necessary (i.e., STOP group). We considered that the appropriate timing for follow-up polysomnography was when the STOP score stopped decreasing. A historical control group was established from consecutive patients without a STOP score.Results In the STOP group (n=57), the median (interquartile range) of STOP scores gradually decreased with OA treatment, from 3 (2-3) to 0 (0-1) (p<0.05). While the apnea hypopnea index (AHI) was improved in both the STOP group (19±10 to 5±4 /hr, p<0.01) and the control group (n=61; 19±7 to 8±7 /hr, p<0.01), there was a significant difference in follow-up AHI between the two groups (p<0.05) after controlling for gender (male), age, body mass index, and baseline AHI: a superior treatment outcome in the STOP group.Conclusions The appropriate timing for follow-up sleep-testing in OSA patients undergoing OA therapy is when the STOP score stopped decreasing. This evaluation using the STOP score partly resolves the current "trial-and-error nature" of OA adjustment and facilitates proper post-treatment sleep-testing.

Experimental study on the influence of model variations on the airway occlusion of an obstructive sleep apnea patient

This study deals with the analysis of model parameters to mimic the airway collapse of an obstructive sleep apnea patient during nasal breathing. Different material properties and geometry variations of a patient-specific airway model are analyzed in detail. The patient-specific airway geometry is obtained from MRI data. A completely rigid model is compared to two partly elastic variations with different elasticities. Furthermore, the influence of the nasal cavities and the treatment effect of a mandibular protrusion are studied. Rigid model parts are 3D-printed and elastic parts cast from silicone. The models are analyzed under the impact of a transient airflow which is realized through a computer controlled piston pump. The results suggest, that, for moderate deformations, the elasticity of the soft tissue replicate influences rather the level of the pressure drop inside the airway than the shape of the pressure curve. The same suggestion can be made for the influence of the nasal cavities. Often, the spatial location of the minimum pressure is taken as the collapse site of the airway geometry. This study demonstrates, that the spatial locations of the minimum pressure and the maximum deformation do not match. This reveals the importance of a coupled approach of soft tissue and airflow analysis in the search of the collapse site and therefore the best treatment option. A treatment effect of the mandibular protrusion can be anticipated with an accurate patient-specific airway model.

The effect of rapid maxillary expansion on the upper airway's aerodynamic characteristics

Background

The effect of rapid maxillary expansion (RME) on the upper airway (UA) has been studied earlier but without a consistent conclusion. This study aims to evaluate the outcome of RME on the UA function in terms of aerodynamic characteristics by applying a computational fluid dynamics (CFD) simulation.

Methods

This retrospective cohort study consists of seventeen cases with two consecutive CBCT scans obtained before (T0) and after (T1) RME. Patients were divided into two groups with respect to patency of the nasopharyngeal airway as expressed in the adenoidal nasopharyngeal ratio (AN): group 1 was comprised of patients with an AN ratio < 0.6 and group 2 encompassing those with an AN ratio ≥ 0.6. CFD simulation at inspiration and expiration were performed based on the three-dimensional (3D) models of the UA segmented from the CBCT images. The aerodynamic characteristics in terms of pressure drop (ΔP), maximum midsagittal velocity (V_ms), and maximum wall shear stress (P_ws) were compared by paired t-test and Wilcoxon test according to the normality test at T0 and T1.

Results

The aerodynamic characteristics in UA revealed no statistically significant difference after RME. The maximum V_ms (m/s) decreased from 2.79 to 2.28 at expiration after RME (P = 0.057).

Conclusion

The aerodynamic characteristics were not significantly changed after RME. Further CFD studies with more cases are warranted.

Predictive Factors for Efficacious Oral Appliance Therapy in Moderate to Severe Obstructive Sleep Apnea Patients

OBJECTIVES/HYPOTHESIS

Oral appliances (OAs) are a treatment for obstructive sleep apnea hypopnea syndrome (OSAHS). The main objective of the study was to determine the predictive factors of OA efficacy. The secondary objective was to measure the efficacy rates and determine OAs' tolerance and dropout.

STUDY DESIGN

Retrospective study.

METHODS

Efficacy results of the OAs based on the apnea hypopnea index (AHI) reduction, complications, and dropout rates were retrospectively collected from 347 patients with a moderate to severe OSAHS treated by a retention OA. The procedure was entirely performed by otolaryngologists.

RESULTS

The AHI with OA was more significantly reduced in patients with a higher initial AHI and a higher initial body mass index but reduction was not related to age and not proportional to the degree of mandibular advancement. The 50% AHI reduction rate after OA was 65.2%, the AHI ≤5/hr rate after OA was 26.1%, and the <50% AHI reduction and residual AHI > 10/hr rate was 50.1%. The OA significantly reduced the mean AHI (-14.9/hr, P < .0001). In 7.8% of patients, the AHI increased with OA. Seven patients (1.5%) experienced adverse effects. Thirty-seven (7.8%) patients stopped using OA mainly because of its ineffectiveness. Advancement can be considered beyond the initial maximal advancement. It can be effective sometimes; however, increasing advancement did not significantly reduce AHI.

CONCLUSIONS

OA is an effective and well-tolerated treatment for moderate to severe OSAHS. This treatment was effective for reduction of the AHI ≥50% in two-thirds of cases studied and it should be considered in more cases.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2089-E2096, 2021.

The effects of mandibular advancement appliance therapy on jaw-closing muscle activity during sleep in patients with obstructive sleep apnea: a 3-6 months follow-up

STUDY OBJECTIVES

The main aim of this study was to investigate the effects of mandibular advancement appliance (MAA) therapy on jaw-closing muscle activity (JCMA) time-related to respiratory arousals, and on JCMA time-related to nonrespiratory arousals in patients with obstructive sleep apnea.

METHODS

Eighteen patients with OSA (mean ± standard deviation = 49.4 ± 9.8 years) with a mean ± standard deviation apnea-hypopnea index of 22.0 ± 16.0 events/h of sleep participated in a randomized controlled crossover trial in which two ambulatory polysomnographic recordings, 1 with an MAA in situ and another without the MAA in situ, were performed. JCMA was quantified as the sum of rhythmic masticatory muscle activities and other orofacial activities.

RESULTS

Significant reductions in the apnea-hypopnea index (Z = -2.984; P = .003), in the respiratory arousal index (Z = -2.896; P = .004), and in the JCMA time-related to respiratory arousal index (Z = -3.434; P = .001) were found with MAA in situ. On the nonrespiratory arousal index, and on the JCMA time-related to nonrespiratory arousal index, MAA had no significant effect (T = 2.23; P = .82; and Z = -0.66; P = .51, respectively).

CONCLUSIONS

This study shows that effective mandibular advancement appliance therapy significantly reduces jaw-closing muscle activities time-related to respiratory arousals in OSA patients. Future studies are needed to confirm these findings in obstructive sleep apnea patients with comorbid sleep bruxism.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: The Effects of Oral Appliance Therapy on Masseter Muscle Activity in Obstructive Sleep Apnea; Identifier: NCT02011425.

A singular oral appliance to treat obstructive sleep apnea in CPAP non-adherent patients

INTRODUCTION

The most prescribed treatment option for Obstructive Sleep Apnea (OSA) is CPAP; however, its adherence is limited. Oral Appliance therapy (OAT) is frequently an option or even an adjuvant, being the mandibular advancement Oral Appliance (OAm) the most used prescription. It modifies the upper airway, improving the airway patency. OAm construction is based on the occlusal plane to disocclusion. In this study, the DIORS® appliance was used, a singular OAm, based on Neuro-Occlusal Rehabilitation concepts, that uses Camper's plane as a disocclusion reference, in order to achieve neuromuscular balance and functional stability.

OBJECTIVE

This study primarily aimed to assess the DIORS® effectiveness in relation to clinical and polysomnographic outcomes. It was also evaluated if the use of DIORS® is as effective as titrated CPAP to treat CPAP non-adherent patients.

METHODS

Twenty patients were included in this study. Objective and subjective clinical data were assessed at a sleep laboratory using all-night polysomnography, and Epworth Sleepiness Scale (ESS), taken at three moments: Baseline, CPAP titration, and using DIORS®. Analysis of respiratory parameters as apnea/hypopnea index (AHI), oxyhemoglobin saturation levels, the arousal index and daytime sleepiness were taken as criteria for a successful OAT.

RESULTS

Respiratory and arousal parameters improved in both therapies, while DIORS® promoted a better ESS.

CONCLUSION

Results from the present work support that DIORS® is a viable and effective adjuvant therapy for patients with moderate to severe OSA non-adherent to CPAP.

Respiratory outcomes after a 1-year treatment of obstructive sleep apnoea with bibloc versus monobloc oral appliances: a multicentre, randomized equivalence trial

Objective: The benefit of bibloc over monobloc appliances in treating obstructive sleep apnoea (OSA) has not been evaluated in randomized trials. We hypothesized that these types of appliances would be equally effective.Material and methods: In this multicentre, randomized equivalence trial, patients with OSA received one type of bibloc or one type of monobloc treatment. At baseline, a 1-night polygraphy study was done, and this was repeated after 1 year. The outcome was any change in the apnoea-hypopnoea index (AHI) and the limits of equivalence between the two devices were set at ±5 AHI units.Results: Of 302 patients, 146 were randomly assigned to bibloc and 156 to monobloc appliances. In 88 and 104 patients, respectively, there were significant reductions in the AHI (p < .001) with a mean change of -16.7 (95% CI -19.4 to -14.1) in the bibloc and -11.8 (-14.9 to -8.7) in the monobloc groups. The proportions of responders defined as having an AHI <10 were 68% and 65% for the bibloc and monobloc groups, respectively. Treatment-related adverse events were mild, transient and the dropouts were more frequent in the bibloc group.Conclusions: Both types of treatments positively and significantly reduced respiratory disturbances, but at the 1-year follow-up, they were not significantly different in treating OSA, with a numerically greater reduction of the AHI value with the bibloc appliance. However, the higher proportion of treatment-related adverse events and higher proportion of dropouts among bibloc users should be balanced against the advantage of a greater reduction in the AHI.

[Oral appliances for obstructive sleep apnoea: What can we expect?]

INTRODUCTION

Mandibular appliances are a treatment option for obstructive sleep apnea. There are many designs, but in the literature they tend to be grouped into a single entity without considering that efficiency, tolerance, compliance, or side effects are inherent in the design of each of them. A more detailed literature review is therefore warranted for the reader who wants to understand the relative effectiveness of each appliance.

STATE OF KNOWLEDGE

We conducted a literature search using the "oral appliance" and "obstructive sleep apnea" criteria on Pubmed, Embase and Cochrane. This allowed us to compare outcome parameters by appliance class and to highlight the rare studies comparing different appliances.

CONCLUSIONS

Mandibular appliances are not a homogeneous entity. Common use includes only appliances designed for propulsion (with rods and jacks) and retention. However, the few comparative studies available do not identify which are the most effective types or the types with an optimal efficacy/tolerance ratio.

PERSPECTIVES

Further appliance comparison studies are needed to determine the most effective type or with an optimal efficacy/tolerance ratio.

Long-Term Objective Adherence to Mandibular Advancement Device Therapy Versus Continuous Positive Airway Pressure in Patients With Moderate Obstructive Sleep Apnea

STUDY OBJECTIVES

Comparable health effects of mandibular advancement device (MAD) and continuous positive airway pressure (CPAP) therapy have been attributed to higher adherence with MAD compared with CPAP therapy. The objective of this study was to make a direct comparison of the objective adherence between MAD and CPAP in patients with moderate obstructive sleep apnea (OSA).

METHODS

Adherence was monitored for 12 months in 59 patients with moderate OSA (apnea-hypopnea index 15-30 events/h) as part of a randomized controlled trial. Objective adherence with MAD was assessed using the TheraMon microsensor. Objective adherence with CPAP was assessed using the built-in registration software with readout on SD card. Self-reported adherence with both therapies was assessed using a questionnaire.

RESULTS

Forty patients (68%) completed the study with the therapy to which they were randomly assigned. Median (interquartile range) objective adherence (h/night) in the 3rd month was 7.4 (5.2-8.2) for MAD and 6.8 (5.7-7.6) for CPAP (P = .41), compared to 6.9 (3.5-7.9) with MAD and 6.8 (5.2-7.6) with CPAP (P = .85) in the 12th month. There were no significant changes between the 3rd and 12th month for both MAD (P = .21) and CPAP (P = .46). Changes in adherence were not significantly different between MAD and CPAP (P = .51). Self-reported adherence was significantly higher with MAD than CPAP at all follow-ups. Self-reported adherence with CPAP was lower than objective CPAP adherence at the 6th and 12th month (P = .02).

CONCLUSIONS

Objective adherence with MAD and CPAP is comparable and consistent over time. Self-reported adherence is higher with MAD than with CPAP giving rise to interesting discrepancy between objective and self-reported adherence with CPAP.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Identifier: NCT01588275.

Effect of mandibular position achieved using an oral appliance on genioglossus activity in healthy adults during sleep

Background

Oral appliances (OAs) are generally designed to displace the mandible anteriorly and downward, to increase the airway patency. The present study aimed to examine the relationship between genioglossus (GG) muscle activity and mandibular position, considering both anterior and vertical displacements during sleep.

Methods

Seven healthy male adults aged 29.4 ± 1.99 years were evaluated. Maxillary and mandibular OAs were fabricated from 2-mm-thick resin plates with pressure-welding. The activity of the left GG was recorded using two silver ball electrodes attached to the lingual edge of the mandibular OA. Respiratory status and right masseter muscle activity were measured by an airflow sensor and surface electrodes, respectively. Electroencephalography was used to determine the sleep status. Stage 2 (the second stage of sleep) was defined as the state of sleeping. Four test conditions with different mandibular positions (0 and 50% anterior protrusion) and bite openings (4 mm and 12 mm) were examined.

Results

GG activity in SL4A (4 mm bite opening, 50% protrusion during sleep) and SL12 (12 mm bite opening, 0% protrusion during sleep) were significantly higher than that in SL4 (4 mm bite opening, 0% protrusion during sleep). Respiratory volume did not significantly differ between all test conditions.

Conclusion

GG activity is influenced not only by anterior protrusion of the mandible but also by vertical displacement during sleep. Thus, when determining the effectiveness of intraoral appliances in the treatment of obstructive sleep apnea, both protrusion and the size of the mandibular opening should be evaluated and taken into account.

The Most Effective Amount of Forward Movement for Oral Appliances for Obstructive Sleep Apnea: A Systematic Review

This systematic review clarifies the amount of effective protrusion in mandibular advancement devices of oral appliances required for obstructive sleep apnea (OSA). The systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Review Manager 5 and GRADEpro were used to combine trials and analyze data. The present review included three studies. In mild to moderate OSA cases, measured using the apnea–hypopnea index (AHI), 50% protrusion was more effective than 75% protrusion. However, 75% protrusion was more effective for severe cases. Sleep stage, Epworth Sleepiness Scale (ESS), snoring index, and side effects significantly differed between the groups. Additionally, 75% protrusion was more effective (AHI: 0.38, 95% CI: −0.89 to 1.65, p = 0.56; sleep stage 3: −1.20, 95% CI: 9.54–7.14, p = 0.78; ESS: 1.07, 95% CI: −0.09 to 2.24, p = 0.07; snoring index: 0.09, 95% CI: 0.05–0.13, p < 0.05; side effects: RR: 1.89, 95% CI: 0.36–9.92, p = 0.45). As per the AHI, 75% protrusion was effective in severe cases, whereas 50% protrusion was effective in moderate cases. Analysis of different surrogate outcomes indicated that 75% protrusion was more effective. Further, well-designed, larger trials should determine the benefits for patients. Additionally, investigations of adherence and side effects with long-term follow-up are needed.

The Efficacy of Device Designs (Mono-block or Bi-block) in Oral Appliance Therapy for Obstructive Sleep Apnea Patients: A Systematic Review and Meta-Analysis

Oral appliance (OA_m) therapy has demonstrated efficacy in treating obstructive sleep apnea (OSA). The aim of this systematic review was to clarify the efficacy of device designs (Mono-block or Bi-block) in OA_m therapy for OSA patients. We performed a meta-analysis using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Two studies (Mono-block OA_m versus Bi-block OA_m) remained eligible after applying the exclusion criteria. When comparing Mono-block OA_m and Bi-block OA_m, Mono-block OA_m significantly reduced the apnea-hypopnea index (2.92; 95% confidence interval (95%CI), 1.26 to 4.58; p = 0.0006), and patient preference for Mono-block OA_m was significantly higher (2.06; 95%CI, 1.44 to 2.06; p < 0.0001). Lowest SpO₂, arousal index, non-REM stage 3, sleep efficiency, Epworth Sleepiness Scale (ESS), Snoring Scale, and side effects were not significantly different between the two groups (lowest SpO₂: -11.18; 95%CI, -26.90 to 4.54; p = 0.16, arousal index: 4.40; 95%CI, -6.00 to 14.80; p = 0.41, non-REM stage 3: -2.00; 95%CI, -6.00 to 14.80; p = 0.41, sleep efficiency: -1.42, 95%CI, -4.71 to 1.86; p = 0.40, ESS: 0.12; 95%CI, -1.55 to 1.79; p = 0.89, Snoring Scale: 0.55; 95%CI, -0.73 to 1.83, p = 0.55, side effects: 1.00, 95%CI, 0.62 to 1.61, p = 1.00). In this systematic review, the use of Mono-block OA_m was more effective than Bi-block OA_m for OSA patients.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.

Heat-moulded versus custom-made mandibular advancement devices for obstructive sleep apnoea: a randomised non-inferiority trial

RATIONALE

Custom-made mandibular advancement devices (MADs) are reported as providing higher efficacy rates compared with thermoplastic heat-moulded MADs but at the price of higher costs and treatment delays.

OBJECTIVE

To determine whether a thermoplastic heat-moulded titratable MAD (ONIRIS; ONIRIS SAS, Rueil Malmaison, France) is non-inferior to a custom-made acrylic titratable MAD (TALI; ONIRIS SAS, Rueil Malmaison, France) for obstructive sleep apnoea (OSA).

METHODS

We conducted a multicentre, open, randomised controlled trial of patients with OSA refusing or not tolerating continuous positive airway pressure (CPAP). Participants were randomly assigned to a thermoplastic heat-moulded titratable device or a custom-made acrylic device for 2 months with stratification by centre and OSA severity. The non-inferiority primary outcome was a ≥50% reduction in apnoea-hypopnoea index (AHI) or achieving AHI <10 events/hour at 2 months. The non-inferiority margin was preset as a difference between groups of 20% for the primary outcome in the per-protocol analysis.

MAIN RESULTS

Of 198 patients (mean age 51 [SD, 12] years; 138 [72.6%] men; mean body mass index 26 [SD, 2.7] kg/m²; mean AHI 26.6/hour [SD, 10.4]), 100 received TALI and 98 ONIRIS. In per-protocol analysis, the response rate was 51.7% in the TALI group versus 53.6% in the ONIRIS group (absolute difference 1.9%; 90% CI: 11% to 15%, within the non-inferiority margin). Effectiveness was the same for severity, symptoms, quality of life and blood pressure reduction. Patients in ONIRIS group reported more side effects and adherence was slightly better with TALI.

CONCLUSION

In patients with OSA refusing or not tolerating CPAP, the thermoplastic heat-moulded titratable MAD was non-inferior in the short-term to the custom-made acrylic MAD.

TRIAL REGISTRATION NUMBER

NCT02348970.

Use of bibloc and monobloc oral appliances in obstructive sleep apnoea: a multicentre, randomized, blinded, parallel-group equivalence trial

Background

The clinical benefit of bibloc over monobloc appliances in treating obstructive sleep apnoea (OSA) has not been evaluated in randomized trials. We hypothesized that the two types of appliances are equally effective in treating OSA.

Objective

To compare the efficacy of monobloc versus bibloc appliances in a short-term perspective.

Patients and methods

In this multicentre, randomized, blinded, controlled, parallel-group equivalence trial, patients with OSA were randomly assigned to use either a bibloc or a monobloc appliance. One-night respiratory polygraphy without respiratory support was performed at baseline, and participants were re-examined with the appliance in place at short-term follow-up. The primary outcome was the change in the apnoea–hypopnea index (AHI). An independent person prepared a randomization list and sealed envelopes. Evaluating dentist and the biomedical analysts who evaluated the polygraphy were blinded to the choice of therapy.

Results

Of 302 patients, 146 were randomly assigned to use the bibloc and 156 the monobloc device; 123 and 139 patients, respectively, were analysed as per protocol. The mean changes in AHI were −13.8 (95% confidence interval −16.1 to −11.5) in the bibloc group and −12.5 (−14.8 to −10.3) in the monobloc group. The difference of −1.3 (−4.5 to 1.9) was significant within the equivalence interval (P = 0.011; the greater of the two P values) and was confirmed by the intention-to-treat analysis (P = 0.001). The adverse events were of mild character and were experienced by similar percentages of patients in both groups (39 and 40 per cent for the bibloc and monobloc group, respectively).

Limitations

The study shows short-term results with a median time from commencing treatment to the evaluation visit of 56 days and long-term data on efficacy and harm are needed to be fully conclusive.

Conclusion

In a short-term perspective, both appliances were equivalent in terms of their positive effects for treating OSA and caused adverse events of similar magnitude.

Trial registration

Registered with ClinicalTrials.gov (#NCT02148510).

Hypoglossal nerve stimulation therapy on peripheral arterial tonometry in obstructive sleep apnea: a pilot study

PURPOSE

Hypoglossal nerve stimulation (HGNS) is being increasingly utilized in the setting of moderate-severe obstructive sleep apnea (OSA). While moderate-severe OSA confers excess cardiovascular risk, the impact of HGNS on cardiovascular requires further investigation. With the advent of peripheral arterial tonometry (PAT), one can non-invasively study real-time changes to the autonomic nervous system. This study evaluates the effect of HGNS therapy on autonomic output, using PAT-integrated polysomnography.

METHODS

Subjects included adult patients undergoing 2-month post-operative HGNS titration studies with PAT-integrated polysomnography. Apneic and hypopneic events with arousal during stage 2 sleep were identified at increasing levels of stimulation. With each event, PAT signal attenuations were recorded, processed, and analyzed.

RESULTS

Nine subjects were enrolled, and eight met inclusion criteria (mean age 67.8 ± 12.4 years; 50% female). The PAT signal did not significantly change before and during stimulation (mean pre-stimulation 43.4 ± 1.7, mean intra-stimulation 41.1 ± 22.5, p = 0.53) in any patient. The ratio of the PAT signal maximum and minimum amplitudes during sleep breathing events largely demonstrated very weak correlation (R² = <0.12). Across all subjects, poor linear correlation was present between HGNS and PAT signal attenuation (R² = 0.028) in both adjusted and unadjusted analyses.

CONCLUSIONS

Using PAT-integrated polysomnography, PAT output does not appear to be affected by HGNS stimulation at clinical thresholds. These findings support the absence of autonomic system alterations by twelfth nerve stimulation and support the clinical use of PAT-based devices for post-HGNS monitoring. Larger studies examining hard cardiovascular endpoints with HGNS are needed.

Perioperative management of the obese surgical patient

INTRODUCTION

The escalation in the prevalence of obesity throughout the world has led to an upsurge in the number of obese surgical patients to whom perioperative care needs to be delivered.

SOURCES OF DATA

After determining the scope of the review, the authors used PubMed with select phrases encompassing the words in the scope. Both preclinical and clinical reports were considered.

AREAS OF AGREEMENT

There were no controversies regarding preoperative management and the intraoperative care of the obese surgical patient.

AREAS OF CONTROVERSY

Is there a healthy obese state that gives rise to the obesity paradox regarding postoperative complications?

GROWING POINTS

This review considers how to prepare for and manage the obese surgical patient through the entire spectrum, from preoperative assessment to possible postoperative intensive care.

AREAS TIMELY FOR DEVELOPING RESEARCH

What results in an obese patient developing 'unhealthy' obesity?