Update on oral appliance therapy

Assessment and management of continuous positive airway pressure therapy in patient with obstructive sleep apnea

Obstructive sleep apnea (OSA) causes excessive daytime sleepiness, impaired daytime functioning, and an increased risk of cardiovascular diseases. Continuous positive airway pressure (CPAP) is a highly effective therapy for moderate to severe OSA. Although CPAP adherence is commonly assessed using a 4-hthreshold, determining the optimal usage time based on clinical outcomes is crucial. While subjective sleepiness often improves with ≥4 h of CPAP usage, an extended duration (≥6 h) may be necessary to impact objective sleepiness. CPAP demonstrated a modest yet clinically meaningful dose-dependent effect on lowering blood pressure. For patients seeking antihypertensive benefits from CPAP therapy, the goal should extend beyond 4 h of use to maximize the therapeutic impact. Recognizing individual variations in sleep duration and responses to CPAP therapy is essential. The adoption of 'individualized goals for CPAP use,' outlining target times for specific outcomes, should also consider an individual's total sleep duration, including periods without CPAP. The impact of CPAP on clinical outcomes may vary, even with the same duration of CPAP use, depending on the period without CPAP use, particularly during the first or second half of sleep. Patients who remove or initiate CPAP midway or have a low CPAP usage frequency may require different forms of guidance. Tailoring patient education to address CPAP usage patterns may be necessary to enhanced satisfaction, self-efficacy, and adherence to therapy. Management of CPAP treatment should be personalized to meet individual needs and adapted based on specific response patterns for achieving treatment efficacy.

Multi-center safety and efficacy study of a negative-pressure intraoral device in obstructive sleep apnea

BACKGROUND

Intraoral devices, with or without negative oral pressure, can stabilize the oropharynx and reduce obstructive sleep apneas. We tested the hypothesis that treatment with the iNAP® Sleep Therapy System, which applies negative oral pressure through an intra-oral appliance, would reduce the severity of obstructive sleep apnea in a multi-center, prospective, first-night-randomized-order cross-over study.

METHODS/PATIENTS

130 patients fulfilled the entry criteria (age <75, AHI 15-55, BMI <33), and 63 entered the primary endpoint cohort (Total Sleep Time ≥4 h/night on the baseline polysomnogram and an oral negative vacuum time maintained by iNAP® ≥ 4 h/night and total sleep time ≥4 h/night during the first treatment study). 54 patients completed a second treatment sleep study at least 28 days after the first sleep study.

RESULTS

Among the primary endpoint cohort (n = 63, age = 53.2 ± 11.3, BMI = 27.1 ± 2.8), 33 patients (52 %; 95 % confidence interval = 40%-64 %, p < 0.001) responded to iNAP treatment according to the Sher criteria (>50 % reduction in AHI and an AHI ≤20 events/hr). The average oxy-hemoglobin saturation increased by 1-2%, and the average percent oxygen desaturation decreased (was less severe) by 1 % while using the iNAP device. The incidence of adverse events, all self-limited, was low. The reduction in the apnea-hypopnea index was durable over the 28-day study. Patients used iNAP on average 5.6 h per night during the study period.

CONCLUSION

The iNAP® Sleep Therapy System achieved a durable benefit in more than half the patients with moderate to severe obstructive sleep apnea and may be considered in patients who object to or failed continuous positive airway pressure.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02698059.

Content quality and reliability of YouTube videos on oral appliance therapy for obstructive sleep apnea: A systematic analysis

INTRODUCTION

YouTube's popularity as a health information source raises concerns about credibility due to the absence of peer review. Therefore, this study assessed the content quality and reliability of YouTube videos related to oral appliance therapy for obstructive sleep apnea (OSA).

METHODS

Videos were systematically searched on August 20, 2023, using terms determined through Google Trends. Videos were included based on predefined criteria and independently assessed by two researchers. Video demographics were extracted. Video quality was evaluated using audio-visual (AV) quality, video information and quality index (VIQI), global quality score (GQS), and reliability using a modified DISCERN tool (mDISCERN). High and low-content videos were defined based on the customized 10-point scoring system. Inter- and intra-examiner reliability of scoring system were calculated.

RESULTS

Most videos were educational (46.3%), presented by dental sleep medicine specialists (42.6%), and aimed at laypersons (63%), with the majority originating from the United States (79.6%). The final 54 videos were categorized as high-content (n = 29, 54%) and low-content (n = 25, 46%). High-content videos had more views, comments, and longer video durations (7.07 ± 6.04 min). Significant differences (p < .05) were observed among high and low-content videos in total VIQI, mDISCERN, GQS, and TCS. Moderate correlations were found between GQS and TCS (r = 0.721), mDISCERN and VIQI (r = 0.649), GQS and VIQI (r = 0.601), and AV quality and VIQI (r = 0.531).

CONCLUSION

The study highlights variable content quality and reliability of YouTube videos on oral appliance therapy for OSA, emphasizing the need for guidelines to enhance their educational value and deliver reliable, evidence-based information to patients.

Modifications in Upper Airway Collapsibility during Sleep Endoscopy with a Mandibular Positioner: Study in Snorers and Obstructive Sleep Apnea Patients

BACKGROUND

Mandibular advancement devices (MADs) are an effective treatment for patients with sleep-related breathing disorders, with variable response. Increasingly more research points to the predictive value of Drug-Induced Sleep Endoscopy (DISE) in patient selection. This study aims to analyze the changes in upper airway collapsibility using a titratable MAD simulator during DISE.

METHODS

This study included 104 patients with simple snoring and obstructive sleep apnea (OSA). The VOTE scale was used to assess the presence of collapses during the DISE both without and with the MAD simulator.

RESULTS

In snorers, there was a decrease in collapses at the level of the soft palate and oropharynx when the advancement was achieved. Patients with mild OSA also showed a decrease in collapses at the base of the tongue. Patients with moderate/severe OSA exhibited significant amelioration at all levels. The levels at which there were residual collapses despite the maneuver were, in order, the velopharynx, oropharynx, epiglottis, and tongue.

CONCLUSIONS

The MAD simulator reduces collapsibility at all levels and in all severity groups. Residual collapses suitable for combined treatments were able to be identified. This highlights the need for individualized patient selection, as upper airway collapsibility exhibits variable improvement or worsening with the MAD simulator regardless of the severity of the condition.

Comparison of efficacy and usability of custom mandibular advancement devices fabricated with the conventional method and digital workflow: A pilot clinical study

PURPOSE

To compare the effects of fabricating methods of custom monoblock mandibular advancement devices (MADs) on usability and efficacy in patients with mild and moderate obstructive sleep apnea (OSA).

MATERIALS AND METHODS

Digitally fabricated custom MADs (dMADs) were produced for 11 OSA participants who had previously used conventionally fabricated custom MADs (cMADs). The participants answered a modified usability questionnaire for both MADs, and the average scores that were given to the questionnaire were evaluated by age, sex, and body mass index (BMI), and the scores of cMADs and dMADs were compared. After 6 months of usage of each MAD, the apnea-hypopnea index (AHI), mean and lowest oxygen saturations, and total sleep time were measured for efficacy assessment. Data were analyzed with Cronbach's alpha, Mann-Whitney U, Kruskal-Wallis, Wilcoxon signed-rank, one-way repeated measures analyses of variance, and Bonferroni tests (α = 0.05).

RESULTS

Cronbach's alpha was found at 0.834 and 0.722 for the conventional and digital questionnaires, respectively. The usability scores of the dMADs were significantly higher than those of cMADs (p = 0.013). There was no difference in usability scores in terms of sex or BMI (p > 0.05). No statistically significant difference was found for cMAD (p = 0.113) among age groups; however, there was a significant difference for dMAD (p = 0.046). The AHI, mean, and lowest oxygen saturation values were significantly affected by MAD usage (p < 0.001). However, total sleep time values did not differ after the MAD treatments (p > 0.05). Significantly lower AHI and significantly higher lowest oxygen saturation values were observed with dMAD, while both appliances led to similar results for mean oxygen saturation and total sleep time values (p > 0.05).

CONCLUSIONS

Participant usability scores were higher for digitally manufactured MADs than conventionally manufactured MADs. However, both conventional and digital MADs were found effective in decreasing the AHI levels and increasing the mean and lowest oxygen saturation values of the participants.

Mandibular advancement devices decrease systolic pressure during the day and night in patients with obstructive sleep apnea: A systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to analyze whether or not mandibular advancement devices (MADs) produce changes in blood pressure in patients with obstructive sleep apnea (OSA) in relation to use time and if the device is used at night or day.

MATERIALS AND METHOD

A systematic review of the literature and meta-analysis was carried out in accordance with PRISMA guidelines. In the bibliographic search, a total of four databases were consulted: PubMed-Medline, Scopus, Web of Science, and Cochrane. Of the 622 articles initially revealed, 160 duplicates were eliminated. After applying the selection criteria, 17 articles were included for the qualitative analysis and 4 for the meta-analysis. The studies were combined using a random effects model with the inverse method of variance, determining the mean differences in systolic and diastolic pressure before and after treatment using the MAD splint as the effect size. Day/night circadian effect and treatment time were analyzed using meta-regression with a mixed-effects model.

RESULTS

MAD treatment was not found to affect diastolic pressure. By combining the four studies with the control group in a meta-analysis (I2 = 75%; z =  - 0.15; p-value = 0.882), the mean difference in diastolic pressure between the MAD group and the control group was estimated at - 0.06 (- 0.86; 0.74). The meta-regression also showed no significant effect of day/night (p = 0.560) or treatment time (p = 0.854) on diastolic pressure. When combining the four studies with the control group (I2 = 84%%; z =  - 1.47; p-value = 0.142), a non-significant mean difference in systolic pressure between the MAD group and the control group of - 0.99 (- 2.31; 0.33) was estimated in the meta-analysis. However, when assessing the effect of day/night or treatment time on systolic blood pressure using a meta-regression, the latter showed significant covariates that reduce systolic blood pressure values in the model at night (p < 0.001) and in relation to treatment time (p < 0.001).

CONCLUSIONS

Only systolic pressure appears to be affected by the use of the MAD in patients with OSA, and this decrease in systolic pressure is greater at night and when treatment time is longer.

Long-term efficacy of mandibular advancement devices in the treatment of adult obstructive sleep apnea: A systematic review and meta-analysis

This study aims to review the long-term subjective and objective efficacy of mandibular advancement devices (MAD) in the treatment of adult obstructive sleep apnea (OSA). Electronic databases such as PubMed, Embase, and Cochrane Library were searched. Randomized controlled trials (RCTs) and non-randomized self-controlled trials with a treatment duration of at least 1 year with MAD were included. The quality assessment and data extraction of the included studies were conducted in the meta-analysis. A total of 22 studies were included in this study, of which 20 (546 patients) were included in the meta-analysis. All the studies had some shortcomings, such as small sample sizes, unbalanced sex, and high dropout rates. The results suggested that long-term treatment of MAD can significantly reduce the Epworth sleepiness scale (ESS) by -3.99 (95%CI -5.93 to -2.04, p<0.0001, I2 = 84%), and the apnea-hypopnea index (AHI) -16.77 (95%CI -20.80 to -12.74) events/h (p<0.00001, I2 = 97%). The efficacy remained statistically different in the severity (AHI<30 or >30 events/h) and treatment duration (duration <5y or >5y) subgroups. Long-term use of MAD could also significantly decrease blood pressure and improve the score of functional outcomes of sleep questionnaire (FOSQ). Moderate evidence suggested that the subjective and objective effect of MAD on adult OSA has long-term stability. Limited evidence suggests long-term use of MAD might improve comorbidities and healthcare. In clinical practice, regular follow-up is recommended.

Pathophysiological mechanisms and therapeutic approaches in obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is a common breathing disorder in sleep in which the airways narrow or collapse during sleep, causing obstructive sleep apnea. The prevalence of OSAS continues to rise worldwide, particularly in middle-aged and elderly individuals. The mechanism of upper airway collapse is incompletely understood but is associated with several factors, including obesity, craniofacial changes, altered muscle function in the upper airway, pharyngeal neuropathy, and fluid shifts to the neck. The main characteristics of OSAS are recurrent pauses in respiration, which lead to intermittent hypoxia (IH) and hypercapnia, accompanied by blood oxygen desaturation and arousal during sleep, which sharply increases the risk of several diseases. This paper first briefly describes the epidemiology, incidence, and pathophysiological mechanisms of OSAS. Next, the alterations in relevant signaling pathways induced by IH are systematically reviewed and discussed. For example, IH can induce gut microbiota (GM) dysbiosis, impair the intestinal barrier, and alter intestinal metabolites. These mechanisms ultimately lead to secondary oxidative stress, systemic inflammation, and sympathetic activation. We then summarize the effects of IH on disease pathogenesis, including cardiocerebrovascular disorders, neurological disorders, metabolic diseases, cancer, reproductive disorders, and COVID-19. Finally, different therapeutic strategies for OSAS caused by different causes are proposed. Multidisciplinary approaches and shared decision-making are necessary for the successful treatment of OSAS in the future, but more randomized controlled trials are needed for further evaluation to define what treatments are best for specific OSAS patients.

Mandibular advancement device: prescription in adult dental sleep medicine - guideline of the German Society of Dental Sleep Medicine

PURPOSE

Obstructive sleep apnea (OSA) may result in severe health onditions, reduces quality of live, and affects high percentages of the adult population. Due to recent changes in the German health care regulations, mandibular advancement devices (MAD) will become available as a treatment option for OSA to a greater extent for general dentists and their patients.

METHODS

A guideline development group consisting of nine members representing four German dental and medical organizations was formed, in order to provide critical information and orientation to the main stakeholders (dentists and patients), regarding the use of MAD for the treatment of OSA within dental sleep medicine.

RESULTS

This guideline aims to inform physicians and dentists, particularly those with acquired qualification/specialization in sleep medicine (or in the diagnosis and treatment of sleep-related breathing disorders), as well as experts, payers, and patients. It delivers recommendations on technical requirements for MAD prescription and fabrication, clinical procedures, maintenance, and follow-up procedures.

CONCLUSION

A MAD should be designed for long-term therapy and must be a custom made, adjustable, bimaxillary retained two-splint system equipped with adjustable protrusive elements. The fabrication in a dental laboratory should be based on dental impressions or scans and three-dimensional registrations of the starting position taken with a bite gauge.

Antero-Posterior Mandibular Excursion in Obstructive Sleep Apnea Patients Treated with Mandibular Advancement Device: A Retrospective Cohort Study

Since obstructive sleep apnea (OSA) management with a mandibular advancement device (MAD) is likely to be life-long, potential changes in mandibular movements during therapy should be investigated. The purpose of this study was to use a method that has already been shown to be reliable in order to determine whether the range of antero-posterior mandibular excursion, the procedure upon which MAD titration is based, varies between baseline (T0) and at least 1 year of treatment (T1). The distance between maximal voluntary protrusion and maximal voluntary retrusion determined using the millimetric scale of the George Gauge was retrospectively collected from the medical records of 59 OSA patients treated with the MAD and compared between T0 and T1. A regression analysis was performed to evaluate the influence of treatment time, MAD therapeutic advancement and the patient's initial characteristics in excursion range variation. A statistically significant increase of 0.80 ± 1.52 mm (mean ± standard deviation, p < 0.001) was found for antero-posterior mandibular excursion. The longer the treatment time (p = 0.044) and the smaller the patient's mandibular excursion at T0 (p = 0.002), the greater the increase was. These findings could be explained by a muscle-tendon unit adaptation to the forward mandibular repositioning induced by the MAD. During MAD therapy, patients can develop a wider range of antero-posterior mandibular excursion, especially those with a smaller initial excursion capacity.

Fabricating a custom monoblock mandibular advancement device by using an open-source nondental CAD software program and additive manufacturing: A dental technique

Custom mandibular advancement devices (MADs) can be fabricated by using either conventional processes or computer-aided design and computer-aided manufacturing (CAD-CAM). The CAD-CAM technique involves digitizing the dental arches of the patients, designing by using a dental CAD software program, and additive manufacturing with a suitable material. This article describes the steps of the design of a custom MAD by using an open-source nondental CAD software program and of the fabrication with additive manufacturing.

Neural Basis of Etiopathogenesis and Treatment of Cervicogenic Orofacial Pain

(1) Background and Objectives: The aim of this narrative review was to analyze the neuroanatomical and neurophysiological basis of cervicogenic pain in cervico-cranial pain syndromes, focusing particularly on cervico-orofacial syndromes as a background for the proper diagnosis and non-surgical treatment. Relevant literature on the topic from past 120 years has been surveyed. (2) Material and Methods: We surveyed all original papers, reviews, or short communications published in the English, Spanish, Czech or Slovak languages from 1900 to 2020 in major journals. (3) Results: The cervicogenic headache originates from the spinal trigeminal nucleus where axons from the C₁–C₃ cervical spinal nerves and three branches of the trigeminal nerve converge (trigeminocervical convergence) at the interneurons that mediate cranio-cervical nociceptive interactions. The role of the temporomandibular joint in the broad clinical picture is also important. Despite abundant available experimental and clinical data, cervicogenic orofacial pain may be challenging to diagnose and treat. Crucial non-surgical therapeutic approach is the orthopedic manual therapy focused on correction of body posture, proper alignment of cervical vertebra and restoration of normal function of temporomandibular joint and occlusion. In addition, two novel concepts for the functional synthesis of cervico-cranial interactions are the tricentric concept of mouth sensorimotor control and the concept of a cervicogenic origin of bruxism. (4) Conclusions: Understanding the basis of neuroanatomical and neurophysiological neuromuscular relations enables an effective therapeutic approach based principally on orthopedic manual and dental occlusal treatment.

Non-CPAP therapy for obstructive sleep apnoea

Treatment of obstructive sleep apnoea in adults is evolving, from a "one treatment fits all" to a more individualised approach. The spectrum of treatment options is broad and heterogeneous, including conservative, technological and pharmaceutical modalities. This raises the questions of which patients these modalities might be useful for, and if there are specific criteria for single or combined treatment. The most commonly used non-CPAP treatment is a mandibular advancement device. Furthermore, it appears from the available evidence that upper airway surgery, bariatric surgery, and maxillomandibular advancement can be effective in particular patient groups and should be indicated more readily in clinical practice. Technically, a tracheotomy is the most effective surgical treatment, but is not socially acceptable and is associated with major side-effects. Other treatment options are emerging, like positional therapy, hypoglossal nerve stimulation, and myofunctional exercises. Drug therapy is also promising when pathophysiological traits are considered. The range of currently available treatment options will be discussed in this review, with emphasis on the selection of appropriate patients, therapeutic efficacy and compliance, and reference to recent guidelines. In the selection process, routine application of drug-induced sleep endoscopy to assess the site(s) of collapse during sleep can increase the success rate of both surgical interventions and oral appliance therapy.

Educational aims

To outline recommendations concerning the proper management of obstructive sleep apnoea (OSA) patients that cannot be treated adequately with continuous positive airway pressure (CPAP) due to intolerance, poor adherence or compliance, or CPAP refusal.To provide information about the selection of appropriate patients for alternative non-CPAP treatment options.To better understand the different aspects of OSA treatment with noninvasive approaches, such as oral appliances, positional therapy, drug treatment and myofunctional therapy, including indications, contraindications, and expected short- and long-term results.To discuss the different surgical options for the treatment of OSA and to provide information on the important issue of proper patient selection for surgery, as most OSA surgical outcomes are associated with the pre-operative assessment of the level(s) of upper airway collapse.

The comparison of two different mandibular positions for oral appliance therapy in patients with obstructive sleep apnea

BACKGROUND

An oral appliance (OA) can alleviate upper airway obstruction by pulling the mandible forward during sleep. While a large mandibular advancement with an OA decreases the number of apnea and hypopnea events, long-term use may cause side effects, such as toothache, stiffness, and pain in the temporomandibular joint.

OBJETIVES

This study aimed to evaluate the effectiveness of different mandibular positions for obstructive sleep apnea (OSA) and determine the optimal therapeutic mandibular position.

METHODS

Thirty-two patients (17 males and 15 females) with mild to moderate OSA participated in this prospective study. All patients were randomly allocated to receive a 50% mandibular advancement or a 75% mandibular advancement with an OA. The pre- and posttreatment apnea-hypopnea index (AHI), apnea index (AI), and Epworth Sleepiness Scale (ESS) were compared. Treatment effectiveness and treatment success were compared between groups.

RESULTS

AHI improved significantly in both groups, and AI improved significantly in the group with 50% mandibular advancement. No significant improvements in the ESS were observed in either group. There was no significant difference in treatment effectiveness between groups. In the proportion of females and males whose treatment was effective in the two groups, females were significantly greater than males.

CONCLUSIONS

For patients with mild to moderate OSA, 50% mandibular advancement is recommended as the initial therapeutic mandibular position. It was suggested that gender differences also affect treatment effectiveness.

An interim oral appliance as a screening tool during drug-induced sleep endoscopy to predict treatment success with a mandibular advancement device for obstructive sleep apnea

Purpose

Previous studies have shown a wide range of efficacy (29 to 71%) of a mandibular advancement device (MAD) in the treatment of obstructive sleep apnea (OSA). Currently, the ability to preselect suitable patients for MAD therapy based on individual characteristics related to upper airway collapsibility is limited. We investigated if the use of non-custom interim MAD during drug-induced sleep endoscopy (DISE) could be a valuable screening tool to predict MAD treatment outcome.

Methods

In a single-center prospective study including a consecutive series of patients with OSA, we compared DISE outcomes with a MAD in situ with polysomnography results after 3 months of using the same MAD that was used during DISE.

Results

Of 41 patients who completed the study, the median apnea–hypopnea index (AHI) was 16.0 events/h [IQR 7.4–23.4]. Respiratory outcomes on polysomnography, including apnea index (AI), total AHI, AHI in supine position, and oxygen desaturation index, all significantly improved after 3 months of MAD treatment. With complete improvement of the upper airway obstruction with the MAD in situ during DISE in supine position, patients were 6.3 times more likely to be a responder to MAD treatment compared to patients with a persisting complete obstruction, although not statistically significant (OR 6.3; 95%CI 0.9–42.7; p = 0.060).

Conclusion

The potential predictive value with regard to MAD therapy outcomes of the use of an interim MAD during DISE would be an important finding, since the prediction of MAD therapy outcome is of great clinical and scientific interest. A study with a larger cohort should be performed to further investigate our findings.

Treatment options in obstructive sleep apnea

Treatment of OSA with CPAP is currently the recommended treatment and has the greatest evidence of efficacy on AHI, symptoms and comorbidities. Symptomatic patients with moderate-severe OSA generally have good adherence to CPAP therapy, while those with mild OSA, female, young and generally paucisymptomatic, have lower CPAP adherence, especially in the medium and long term. The recent identification of different clinical and pathophysiological phenotypes of OSA has paved the way for alternative treatments to CPAP, leading to an increasingly personalized therapy. Weight loss and lifestyle modifications are highly recommended in all obese or overweight patients. Mandibular advancement devices (MAD), positional therapy (PT) and hypoglossal nerve stimulation (HSN) are recent and personalized alternative therapies on which there is promising and encouraging data but with still little strong scientific evidence. The purpose of this review is to compare the efficacy, adherence and costs of various therapeutic options for OSA patients in the light of recent evidence and to provide useful guidance for specialists.

Dental and Skeletal Side Effects of Oral Appliances Used for the Treatment of Obstructive Sleep Apnea and Snoring in Adult Patients—A Systematic Review and Meta-Analysis

Background: Mandibular advancement devices for obstructive sleep apnea treatment are becoming increasingly popular among patients who do not prefer CPAP devices or surgery. Our study aims to evaluate the literature regarding potential dental and skeletal side effects caused by mandibular advancement appliances used for adult OSA treatment. Methods: Electronic databases were searched for published and unpublished literature along with the reference lists of the eligible studies. Randomized clinical trials and non-randomized trials assessing dental and skeletal changes by comparing cephalometric radiographs were selected. Study selection, data extraction, and risk of bias assessment were performed individually and in duplicate. Fourteen articles were finally selected (two randomized clinical trials and 12 non-randomized trials). Results: The results suggest that mandibular advancement devices used for OSA treatment increase the lower incisor proclination by 1.54 ± 0.16°, decrease overjet by 0.89 ± 0.04 mm and overbite by 0.68 ± 0.04 mm, rotate the mandible downward and forward, and increase the SNA angle by to 0.06 ± 0.03°. The meta-analysis revealed high statistical heterogeneity. Conclusions: The MADs affect the lower incisor proclination, overjet, overbite, the rotation of the mandible and the SNA angle. More randomized clinical trials providing high-quality evidence are needed to support those findings.

Effectiveness of a Uniquely Designed Oral Appliance on Obstructive Sleep Apnea Control: A Pilot Study

Objectives  Obstructive sleep apnea is an inflammatory, chronic, and evolutive disease often needing adequate treatment and follow-up. The oral appliance (OA) is an accepted alternative therapy for obstructive sleep apnea (OSA) control. Due to greater adherence, OA with mandibular advancement (OA _m ) is being recommended treatment for patients who refuse or do not tolerate continuous positive airway pressure. The mode of action of OA _m is to promote the advancement of the mandible or tongue with a subsequent increase in the tone of the pharyngeal muscles and the permeability of the upper airway, but most OA _m use conventional models as reference, analogic, or digital, dissociating dental arches of the skull structures.

Materials and Methods  A retrospective longitudinal study of 33 OSA patient treated with a different OA _m , that use Camper plane as reference with skull structures for dental arches disocclusion, where polysomnographic, cephalometric measures, and subjective data from questionnaires pre- and post-treatment were assessed and correlated. Descriptive analysis, correlated Chi-square tests, and basic statistics were used. Generalized linear mixed model for repeated measure and post hoc Tukey–Kramer test compares the variables pre- and post-treatment. Shapiro–Wilk test and Pearson's correlation coefficients were used. All statistical tests were set in 5% level of significance.

Results  Regarding polysomnography data, there was a significant association between apnea hypopnea index (AHI) with oxygen saturation, arousal index (AI) and the maximum heartbeats, and sleep improvement and health risk reduction. Additionally, from cephalometric data, it was found a significant association between the tongue posture with the soft palate, hioyd-C3 and, lower and posterior airway. When both parameters are correlated, there are a significant dependent association with hyoid bone position with AHI and AI. The limitation of this study was the two-dimensional image used without provide volumetric measurements, but this limitation was reduced with the follow-up polysomnography parameters.

Conclusion  In this pilot study, DIORS OA _m as an uniquely designed device using Camper plane as a reference for disocclusion was effective in the control of OSA.

Hypoxic Regulation of the Large-Conductance, Calcium and Voltage-Activated Potassium Channel, BK

Hypoxia is a condition characterized by a reduction of cellular oxygen levels derived from alterations in oxygen balance. Hypoxic events trigger changes in cell-signaling cascades, oxidative stress, activation of pro-inflammatory molecules, and growth factors, influencing the activity of various ion channel families and leading to diverse cardiovascular diseases such as myocardial infarction, ischemic stroke, and hypertension. The large-conductance, calcium and voltage-activated potassium channel (BK) has a central role in the mechanism of oxygen (O₂) sensing and its activity has been related to the hypoxic response. BK channels are ubiquitously expressed, and they are composed by the pore-forming α subunit and the regulatory subunits β (β1–β4), γ (γ1–γ4), and LINGO1. The modification of biophysical properties of BK channels by β subunits underly a myriad of physiological function of these proteins. Hypoxia induces tissue-specific modifications of BK channel α and β subunits expression. Moreover, hypoxia modifies channel activation kinetics and voltage and/or calcium dependence. The reported effects on the BK channel properties are associated with events such as the increase of reactive oxygen species (ROS) production, increases of intracellular Calcium ([Ca²⁺]_i), the regulation by Hypoxia-inducible factor 1α (HIF-1α), and the interaction with hemeproteins. Bronchial asthma, chronic obstructive pulmonary diseases (COPD), and obstructive sleep apnea (OSA), among others, can provoke hypoxia. Untreated OSA patients showed a decrease in BK-β1 subunit mRNA levels and high arterial tension. Treatment with continuous positive airway pressure (CPAP) upregulated β1 subunit mRNA level, decreased arterial pressures, and improved endothelial function coupled with a reduction in morbidity and mortality associated with OSA. These reports suggest that the BK channel has a role in the response involved in hypoxia-associated hypertension derived from OSA. Thus, this review aims to describe the mechanisms involved in the BK channel activation after a hypoxic stimulus and their relationship with disorders like OSA. A deep understanding of the molecular mechanism involved in hypoxic response may help in the therapeutic approaches to treat the pathological processes associated with diseases involving cellular hypoxia.

Mandibular Advancement Splint Therapy

Mandibular advancement splint (MAS) therapy is the leading alternative to continuous positive airway pressure (CPAP) therapy for the treatment of obstructive sleep apnoea. A MAS is an oral appliance which advances the mandible in relation to the maxilla, thus increasing airway calibre and reducing collapsibility. Although it is less effective than CPAP in reducing the apnoea-hypopnoea index (AHI), it has demonstrated equivalence to CPAP in a number of key neurobehavioural and cardiovascular health outcomes, perhaps due to increased tolerability and patient adherence when compared to CPAP. However, response to MAS is variable, and reliable prediction tools for patients who respond best to MAS therapy have thus far been elusive; this is one of the key clinical barriers to wider uptake of MAS therapy. In addition, the most effective MAS devices are custom-made by a dentist specialising in the treatment of sleep disorders, which may present financial or accessibility barriers for some patients. MAS devices are generally well tolerated but may have side effects including temporomandibular joint (TMJ) dysfunction, hypersalivation, tooth pain and migration as well as occlusal changes. A patient-centred approach to treatment from a multidisciplinary team perspective is recommended. Evidence-based clinical practice points and areas of future research are summarised at the conclusion of the chapter.

Quantification of the Impact of Intraoperative Ultrasound in Transoral Robotic Tongue Base Reduction

OBJECTIVES/HYPOTHESIS

Transoral robotic surgery (TORS) in the base of the tongue (BOT) reduction has been shown to decrease the apnea-hypopnea index (AHI) and improve daytime sleepiness in obstructive sleep apnea (OSA) patients. Intraoperative ultrasound (IOU) can be employed to guide the surgery and prevent massive bleeding.

STUDY DESIGN

Cohort study with historical control.

METHODS

A cohort study to compare the outcomes between OSA patients who received TORS with and without IOU assistance.

RESULTS

From 2016 to 2019, this study enrolled 80 OSA patients who underwent TORS in BOT: 57 in the IOU(+) and 23 in IOU(-) groups. The TORS with IOU presented with shorter operative time, less blood loss, and greater excised BOT volume. The IOU(+) group had greater improvement in the AHI and subjective questionnaire evaluation. The excised volume of BOT was significantly associated with the change in AHI.

CONCLUSION

The IOU could improve outcomes in BOT reduction surgery without raising the risk of surgical complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

The Many Fronts of Battling Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a breathing disorder during sleep secondary to collapsing upper airways that leads to a significant decrease or a complete cessation of airflow despite an effort to breathe. As the name suggests, an obstruction, likely caused by an inherited narrow airway, is the most common cause. But there are less known factors that may contribute to the worsening of OSA. We present a case of very severe OSA contributed by weight gain, opioid use, and anterior cervical discectomy and fusion (ACDF), in addition to a genetically narrow airway. This case highlights the importance of battling OSA on many different fronts. Our patient eventually was able to stop positive airway pressure (PAP) therapy, once the contributing factors were addressed appropriately.

Mandibular advancement device use in obstructive sleep apnea: ORCADES study 5-year follow-up data

STUDY OBJECTIVES

Mandibular advancement devices (MADs) are an alternative to continuous positive airway pressure for the management of obstructive sleep apnea (OSA). The ORthèse d'avanCée mAndibulaire dans le traitement en DEuxième intention du SAHOS sévère (ORCADES) study is investigating the long-term effectiveness of MAD therapy in patients with OSA who refused or were intolerant of continuous positive airway pressure. Five-year follow-up data are presented.

METHODS

Data were available in 172 of 331 patients treated with a custom-made computer-aided design/computer-aided manufacturing biblock MAD (Narval CC; ResMed, Saint-Priest, France). The primary end point was treatment success (≥50% decrease in apnea-hypopnea index from baseline).

RESULTS

Five-year treatment success rates were 52% overall and 25%, 52%, and 63%, respectively, in patients with mild, moderate, or severe OSA. This reflects a decline over time vs 3-6 months (79% overall) and 2 years (68%). Rates declined in all patient subgroups but to the greatest extent in patients with mild OSA. The slight worsening of respiratory parameters over time was not associated with any relevant changes in sleepiness and symptoms. Moderate or severe OSA at baseline, treatment success at 3-6 months, and no previous continuous positive airway pressure use were significant independent predictors of 5-year treatment success on multivariate analysis. No new safety signals emerged during long-term follow-up. The proportion of patients using their MAD for ≥4 h/night on ≥4 days/wk was 93.3%; 91.3% of patients reported device use of ≥6 h/night at 5 years. At 5-year follow-up, 96.5% of patients reported that they wanted to continue MAD therapy.

CONCLUSIONS

Long-term MAD therapy remained effective after 5 years in >50% of patients, with good levels of patient satisfaction and adherence.

CITATION

Vecchierini MF, Attali V, Collet JM, et al. Mandibular advancement device use in obstructive sleep apnea: ORCADES study 5-year follow-up data. J Clin Sleep Med. 2021;17(8):1695-1705.

Long-term dentoskeletal side effects of mandibular advancement therapy in patients with obstructive sleep apnea: data from the Pays de la Loire sleep cohort

OBJECTIVES

Mandibular advancement devices (MADs) are the main therapeutic alternative to continuous positive airway pressure for obstructive sleep apnea. Our aim was to evaluate the long-term dentoskeletal side effects of MADs and to identify the predictive factors for these side effects.

MATERIALS AND METHODS

Patients from the Pays de la Loire cohort treated with a custom-made MAD for at least 1 year were included in this retrospective study. Digital cephalometric analyses were performed at baseline and at follow-up.

RESULTS

We included a total of 117 patients, treated with a MAD for a median [interquartile range] of 4.6 [2.6-6.6] years. The main significant side effects were a decrease in overbite (- 0.5 ± 1 mm), overjet (- 0.7 ± 1 mm) and maxillary incisor inclination (- 2.5 ± 2.8°) and an increase in mandibular incisor inclination (+ 2.2 ± 2.7°). Subjective side effects were not linked to the observed dentoskeletal changes. Current smokers were at higher risk of overjet modifications. A pre-existing anterior open-bite was associated with a greater decrease in overbite. Treatment duration was associated with a more pronounced mandibular incisor proclination. Propulsion was negatively associated with maxillary incisor retroclination.

CONCLUSIONS

Long-term dentoskeletal side effects were mainly moderate dental side effects. Some predictive factors were shown to be associated with more pronounced changes. Subjective side effects did not appear to be reliable tools to detect dentoskeletal side effects.

CLINICAL RELEVANCE

Regular follow-up with clinical examination and regular radiographs is mandatory. The predictive factors could be of interest for a better selection of patients and to individualize follow-up.

Variations in funding for treatment of obstructive sleep apnoea in England

OBJECTIVES

This study aimed to review the funding policies of clinical commissioning groups for treatment of obstructive sleep apnoea in England.

METHODS

Published policies from a randomly selected sample of 60 out of 190 clinical commissioning groups were reviewed.

RESULTS

Continuous positive airway pressure was funded based on a clinical assessment or according to criteria that were in line with national guidelines in most clinical commissioning groups (49 of 60), with 11 clinical commissioning groups offering no policy. Mandibular advancement devices, tonsillectomy and nasal surgery were funded based on a clinical assessment or certain criteria in 16, 25 and 16 clinical commissioning groups, respectively. In contrast, only one clinical commissioning group provided funding for soft palate, tongue base or mandibular surgery. Hypoglossal nerve stimulation was not mentioned in any clinical commissioning group's policy.

CONCLUSION

Although most clinical commissioning groups provide funding for the use of continuous positive airway pressure, the availability of funding for other obstructive sleep apnoea treatment modalities is heterogeneous, leaving continuous positive airway pressure intolerant patients with limited therapeutic options in some regions.

Mandibular Advancement Devices for OSA: An Alternative to CPAP?

Obstructive sleep apnea (OSA) is a prevalent condition causing unrefreshing sleep and excessive daytime sleepiness. It has individual socioeconomic impacts and, through association with increased risk of road traffic accidents, diabetes, and cardiovascular disease, OSA is a public health issue. Continuous positive airway pressure (CPAP) is the first-line treatment for moderate-to-severe OSA. It is effective in improving excessive daytime sleepiness and quality of life. There is also evidence that CPAP therapy has cardiovascular benefits although nature and extent remain uncertain. Despite its benefits, a significant proportion of patients are unable to tolerate CPAP. There are also patients with mild but symptomatic disease, for whom CPAP is usually not available or appropriate, so there is a need for other treatment options. Mandibular advancement devices (MADs) offer an effective alternative to CPAP and can improve daytime symptoms and quality of life. There are many devices available, representing a range of complexity and cost. It is challenging to properly evaluate the effectiveness of this ever-evolving range. The more basic MADs are cheaper and more accessible but are less well tolerated. More complex devices are better tolerated and may be more effective. However, they are more expensive and often require dental expertise, so access is more limited. Efforts continue to try to improve accessibility to effective MAD therapy. Alongside increasing awareness, this may be facilitated by developing and refining devices that could be fitted by non-dental clinicians, and potentially by patients themselves. Research efforts need to focus on determining how to efficiently identify patients who are likely to respond to MAD therapy, so as to improve clinical and cost-effectiveness of OSA therapy overall.