Reliability of an adherence monitoring sensor embedded in an oral appliance used for treatment of obstructive sleep apnoea.

The aim of this study was to test whether digitally registered use of a mandibular advancement device (MAD) by a built-in thermal sensor was reliable compared to a self-reported diary of MAD use. Eighty consecutive patients referred to a specialist outpatient sleep medicine clinic (HUS) were recruited. Patients of both genders, aged from 25 to 70 years with a diagnosis of mild, moderate or severe, were included. All participants signed a written informed consent when they received the MAD. For the purpose of this reliability study, we found it sufficient to include the first 30 nights of MAD use in the reliability analysis. At the 30th night follow-up visit, the self-reported diary with duration of MAD use was returned and data on the duration of MAD use with the built-in sensor were retrieved. From a total of 2400 nights, complete data from both methods were retrieved for 2108 nights (84.6%). Missing data were largely a result of missing self-reported diaries, whereas technical failure occurred in 6 nights (0.002%). The relative reliability was very high with ICC3,1 0.847, and the absolute reliability for digitally registered MAD usage was calculated to -0.17 (95% CI: 1.47 to -1.81) hours in decimal conversion. Objectively collected data from built-in thermal sensors in MADs are as reliable as those of the self-report assessments. This opens new possibilities for more accurate measurements of MAD adherence.

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

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

Change of mandibular position during two-phase orthodontic treatment of skeletal class II in the Chinese population.

The aim of this study was to evaluate the change in mandibular position during a two-phase orthodontic treatment of skeletal Class II malocclusion. Thirty consecutively treated Chinese male adolescents who had undergone two-phase treatment with Herbst appliance and fixed appliance and fulfilled the specific selection criteria were sampled. Cephalograms taken at T0 (before treatment), T1 (at the end of functional appliance treatment), and T2 (at the end of fixed appliance treatment) were analyzed. The change in sagittal positioning of the mandible was 6.8 ± 3.44 mm in phase I (T0-T1), 0.4 ± 2.79 mm in phase II (T1-T2), and 7.2 ± 4.61 mm in total. The mandible came forward in 100% of the patients at T1. In phase II, it came forward in one-third (positive group) remained unchanged in one-third (stable group) and went backward in one-third (negative group) of the patients. At T2, it came forward twice as much in the positive group compared to the negative group. Mandibular length was significantly increased in 100% of the patients in both phases. In conclusion, during the treatment with functional appliance, the mandibular prognathism increases in all patients, whereas during the treatment with fixed appliance there is no significant change in mandibular prognathism.

Health outcomes of continuous positive airway pressure versus oral appliance treatment for obstructive sleep apnea: a randomized controlled trial.

RATIONALE: Continuous positive airway pressure (CPAP) and mandibular advancement device (MAD) therapy are commonly used to treat obstructive sleep apnea (OSA). Differences in efficacy and compliance of these treatments are likely to influence improvements in health outcomes. OBJECTIVES: To compare health effects after 1 month of optimal CPAP and MAD therapy in OSA. METHODS: In this randomized crossover trial, we compared the effects of 1 month each of CPAP and MAD treatment on cardiovascular and neurobehavioral outcomes. MEASUREMENTS AND MAIN RESULTS: Cardiovascular (24-h blood pressure, arterial stiffness), neurobehavioral (subjective sleepiness, driving simulator performance), and quality of life (Functional Outcomes of Sleep Questionnaire, Short Form-36) were compared between treatments. Our primary outcome was 24-hour mean arterial pressure. A total of 126 patients with moderate-severe OSA (apnea hypopnea index [AHI], 25.6 [SD 12.3]) were randomly assigned to a treatment order and 108 completed the trial with both devices. CPAP was more efficacious than MAD in reducing AHI (CPAP AHI, 4.5 ± 6.6/h; MAD AHI, 11.1 ± 12.1/h; P < 0.01) but reported compliance was higher on MAD (MAD, 6.50 ± 1.3 h per night vs. CPAP, 5.20 ± 2 h per night; P < 0.00001). The 24-hour mean arterial pressure was not inferior on treatment with MAD compared with CPAP (CPAP-MAD difference, 0.2 mm Hg [95% confidence interval, -0.7 to 1.1]); however, overall, neither treatment improved blood pressure. In contrast, sleepiness, driving simulator performance, and disease-specific quality of life improved on both treatments by similar amounts, although MAD was superior to CPAP for improving four general quality-of-life domains. CONCLUSIONS: Important health outcomes were similar after 1 month of optimal MAD and CPAP treatment in patients with moderate-severe OSA. The results may be explained by greater efficacy of CPAP being offset by inferior compliance relative to MAD, resulting in similar effectiveness. Clinical trial registered with https://www.anzctr.org.au (ACTRN 12607000289415).

Effectiveness of treatment apnea-hypopnea index: a mathematical estimate of the true apnea-hypopnea index in the home setting.

PURPOSE: To present a new measurement instrument, the Effectiveness of Treatment Apnea-Hypopnea Index (ET-AHI), which the authors developed to determine an estimate of the therapeutic control of obstructive sleep apnea (OSA). MATERIALS AND METHODS: The authors retrospectively evaluated a cohort of patients with OSA who initially attempted to use continuous positive airway pressure (CPAP) therapy and subsequently underwent maxillomandibular advancement (MMA) surgery. The ET-AHI calculations were performed to estimate the level of CPAP adherence that would be necessary to achieve equivalence with the MMA surgical result and to reach effective AHIs of 5 and 15. RESULTS: The sample was composed of 37 adult patients (mean age, 44.2 ± 9.0 yr; 73% men) with moderate to severe OSA (baseline AHI, 56.3 ± 22.6). CPAP therapy was highly efficacious (CPAP titration AHI, 4.3 ± 5.9), but no patient could adequately adhere to treatment. MMA produced a significant decrease in OSA (AHI after MMA, 11.6 ± 7.4). The ET-AHI calculations predicted that an 86% adherence rate with CPAP would be necessary to achieve equivalence with MMA, whereas adherence rates of 99% and 79% may be required to achieve effective AHIs of 5 and 15, respectively. CONCLUSIONS: The ET-AHI has the potential to significantly affect the care of patients with OSA because it may provide the treating clinician with a valuable tool to estimate the control of OSA for any therapeutic intervention. How closely the ET-AHI predicts the true effective AHI in the home setting requires further validation.

[Oral appliances for obstructive sleep apnoea: What can we expect?] / Orthèses d'avancée mandibulaire et syndrome d'apnées-hypopnées obstructives du sommeil : qu'en attendre ? Revue de la littérature, comparaison par design.

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.

Mandibular advancement splint titration in obstructive sleep apnoea.

INTRODUCTION: Mandibular advancement splints (MAS) allowing self-adjustment may be better tolerated, but the optimum titration protocol needs systematic study. AIM: The aims of the study are to assess the effectiveness of a titratable MAS device in consecutive patients with body mass index (BMI) < 35 kg/m(2) and obstructive sleep apnoea [OSA, apnoea-hypopnoea index (AHI) 10-40/h] and compare two methods of adjustment [self-adjustment or adjustment after polysomnographic (PSG) feedback]. MATERIALS AND METHODS: Twenty-eight patients (24 M, mean age 49 years, mean BMI 27.6 kg/m(2)) with symptomatic (Epworth Sleepiness score > 8/24, snoring, choking or poor sleep quality) OSA (mean AHI 25.7/h, range 10-46/h) had a MAS set at 70% maximal protrusion and were randomised to subjective self-adjustment for 6 weeks (n = 16) or objective adjustment (n = 12; fixed position for 3 weeks, then PSG based feedback at 3 weeks with self-adjustment instructions). Primary outcome variable (AHI) and OSA symptoms were compared by t tests and chi-squared tests at baseline and after 6 weeks. Resolution of apnoea was defined as AHI < 5/h; improvement was defined as AHI decreased by >50% but still >5/h. RESULTS: The groups had similar baseline demographics, OSA severity and occlusal type. MAS therapy improved or resolved OSA in 20 out of 28 (71%) and was reportedly used nightly by 91% of the objective group and 63% of the subjective group (p = 0.04). MAS were used all night by 75% of the objective group and 69% of the subjective group (p > 0.05). MAS adjustment following PSG feedback did not lower AHI further from 3 weeks (baseline 26.5 +/- 12.0/h, 3 weeks 15.3 +/- 13.5/h p = 0.01, 6 weeks 11.7 +/- 10.0/h, p = 0.11). The overall improvement was similar to that achieved with subjective adjustment (baseline AHI 25.4 +/- 7.4/h, 6 weeks 14.3 +/- 10.7/h, p = 0.0002). Symptomatic benefit was reported by both groups. CONCLUSION: In selected patients, titratable MAS improved or resolved OSA in the majority of patients and was well tolerated. PSG-based feedback at 3 weeks allowed objective confirmation of efficacy and increased device use but did not result in greater improvement in AHI or symptoms. Neither titration method was significantly superior for us to provide firm endorsement. However, we recommend a follow-up sleep study to confirm MAS efficacy.

Clinical- and Cost-Effectiveness of a Mandibular Advancement Device Versus Continuous Positive Airway Pressure in Moderate Obstructive Sleep Apnea.

STUDY OBJECTIVES: Limited evidence exists on the cost-effectiveness of mandibular advancement device (MAD) compared to continuous positive airway pressure (CPAP) therapy in moderate obstructive sleep apnea (OSA). Therefore, this study compares the clinical and cost-effectiveness of MAD therapy with CPAP therapy in moderate OSA. METHODS: In a multicentre randomized controlled trial, patients with an apnea-hypopnea index (AHI) of 15 to 30 events/h were randomized to either MAD or CPAP. Incremental cost-effectiveness and cost-utility ratios (ICER/ICUR, in terms of AHI reduction and quality-adjusted life-years [QALYs, based on the EuroQol Five-Dimension Quality of Life questionnaire]) were calculated after 12 months, all from a societal perspective. RESULTS: In the 85 randomized patients (n = 42 CPAP, n = 43 MAD), AHI reduction was significantly greater with CPAP (median reduction AHI 18.3 [14.8-22.6] events/h) than with MAD therapy (median reduction AHI 13.5 [8.5-18.4] events/h) after 12 months. Societal costs after 12 months were higher for MAD than for CPAP (mean difference €2.156). MAD was less cost-effective than CPAP after 12 months (ICER -€305 [-€3.003 to €1.572] per AHI point improvement). However, in terms of QALY, MAD performed better than CPAP after 12 months (€33.701 [-€191.106 to €562.271] per QALY gained). CONCLUSIONS: CPAP was more clinically effective (in terms of AHI reduction) and cost-effective than MAD. However, costs per QALY was better with MAD as compared to CPAP. Therefore, CPAP is the first-choice treatment option in moderate OSA and MAD may be a good alternative. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Identifier: NCT01588275.

Predictors of Side Effects With Long-Term Oral Appliance Therapy for Obstructive Sleep Apnea.

STUDY OBJECTIVES: The aim of this study was to investigate the predictors of dental changes associated with long-term treatment with oral appliances (OAs) in patients with obstructive sleep apnea (OSA). METHODS: This was a retrospective study to investigate Japanese patients with OSA receiving long-term treatment with OAs. Comparisons of cephalometric analysis were carried out between the initial and follow-up assessments of dental and skeletal changes. Based on dental changes, predictors that may cause side effects were investigated. RESULTS: A total of 64 patients (average age at start of treatment: 57.7 ± 14.2 years, 44 males) were included in this study. The average duration of treatment was 4.3 ± 2.1 years. Over the total treatment period, there was a significant reduction in overjet (OJ) (1.5 ± 1.3 mm) and overbite (0.90 ± 1.5 mm), and an increase in the lower incisor line to the mandibular plane (3.1 ± 5.4°). A larger reduction in OJ of ≥ 1 mm was associated with treatment duration, use frequency, and mandibular advancement of the OAs. In addition to these predictive factors, the number of teeth was correlated with the amount of OJ reduction. CONCLUSIONS: For long-term treatment with OAs, the risk of dental side effects should be considered, such as a reduction in OJ. A small number of maxillary teeth, as well as the factors associated with OAs, including treatment duration, use frequency, and mandibular advancement of the OAs, was correlated with an increased rate of OJ reduction. COMMENTARY: A commentary on this article appears in this issue on page 7.

A Comparison of Different Success Definitions in Non-Continuous Positive Airway Pressure Treatment for Obstructive Sleep Apnea Using Cardiopulmonary Coupling.

STUDY OBJECTIVES: The definition and the criteria for the successful treatment of obstructive sleep apnea vary, depending on the study. This study aimed to compare different success criteria of non-continuous positive airway pressure (non-CPAP) treatment for obstructive sleep apnea in terms of sleep quality by using cardiopulmonary coupling. METHODS: We included 98 patients who had been treated with sleep surgery or with a mandibular advancement device at our sleep clinic from January 2011 to March 2013. The success and failure groups were divided by 6 criteria that have been used in the literature. The validity of each of the 6 criteria was evaluated by cardiopulmonary coupling-based sleep quality. RESULTS: The parameters of cardiopulmonary coupling indicated that sleep quality improved with non-CPAP treatment: low-frequency coupling decreased from 57.4% ± 17.7% to 46.9% ± 16.5%, whereas high-frequency coupling increased from 30.2% ± 17.1% to 37.4% ± 16.7%. In multiple regression analysis, only the criterion of a reduction in the apnea-hypopnea index greater than 50% was significantly associated with sleep quality improvement (p = 0.016; 95% confidence interval, 1.008-1.076 in the high-frequency coupling increment; p = 0.001; 95% confidence interval, 1.025-1.099 in the low-frequency coupling decrement). CONCLUSIONS: Cardiopulmonary coupling analysis showed that a reduction in the apnea-hypopnea index of more than 50% might be the optimal criterion to determine the success or failure of non-CPAP treatment in terms of sleep quality.

Testing a better method of predicting postsurgery soft tissue response in Class II patients: A prospective study and validity assessment.

OBJECTIVE: (1) To perform a prospective study using a new set of data to test the validity of a new soft tissue prediction method developed for Class II surgery patients and (2) to propose a better validation method that can be applied to a validation study. MATERIALS AND METHODS: Subjects were composed of two subgroups: training subjects and validation subjects. Eighty Class II surgery patients provided the training data set that was used to build the prediction algorithm. The validation data set of 34 new patients was used for evaluating the prospective performance of the prediction algorithm. The validation was conducted using four validation methods: (1) simple validation and (2) fivefold, (3) 10-fold, and (4) leave-one-out cross-validation (LOO). RESULTS: The characteristics between the training and validation subjects did not differ. The multivariate partial least squares regression returned more accurate prediction results than the conventional method did. During the prospective validation, all of the cross-validation methods (fivefold, 10-fold, and LOO) demonstrated fewer prediction errors and more stable results than the simple validation method did. No significant difference was noted among the three cross-validation methods themselves. CONCLUSION: After conducting a prospective study using a new data set, this new prediction method again performed well. In addition, a cross-validation technique may be considered a better option than simple validation when constructing a prediction algorithm.

Accuracy of three-dimensional soft tissue simulation in bimaxillary osteotomies.

The purpose of this study was to evaluate the accuracy of an algorithm based on the mass tensor model (MTM) for computerized 3D simulation of soft-tissue changes following bimaxillary osteotomy, and to identify patient and surgery-related factors that may affect the accuracy of the simulation. Sixty patients (mean age 26.0 years) who had undergone bimaxillary osteotomy, participated in this study. Cone beam CT scans were acquired pre- and one year postoperatively. The 3D rendered pre- and postoperative scans were matched. The maxilla and mandible were segmented and aligned to the postoperative position. 3D distance maps and cephalometric analyses were used to quantify the simulation error. The mean absolute error between the 3D simulation and the actual postoperative facial profile was 0.81 ± 0.22 mm for the face as a whole. The accuracy of the simulation (average absolute error ≤2 mm) for the whole face and for the upper lip, lower lip and chin subregions were 100%, 93%, 90% and 95%, respectively. The predictability was correlated with the magnitude of the maxillary and mandibular advancement, age and V-Y closure. It was concluded that the MTM-based soft tissue simulation for bimaxillary surgery was accurate for clinical use, though patients should be informed of possible variation in the predicted lip position.

Technical factors accounting for stability of a bilateral sagittal split osteotomy advancement: wire osteosynthesis versus rigid fixation.

OBJECTIVE: Relapse after bilateral sagittal split osteotomy has been attributed to various technical factors that are inherent in the surgical procedure. The purpose of this article was to analyze technical factors that predispose to relapse when wire or rigid fixation is used. STUDY DESIGN: Patients were randomized to either rigid or wire osteosynthesis. Cephalometric radiographs were obtained and digitized at multiple time periods before and after surgery. Data were analyzed through use of 2-sample t tests and stepwise regression analyses. RESULTS: Multivariate analysis indicated that the following factors correlated with relapse: initial advancement, change in ramus in inclination, change in the mandibular plane, and fixation type. CONCLUSIONS: Relapse increased with the amount of initial advancement and, to a lesser extent, with control of the proximal segment and change in the mandibular plane. These factors are similar for wire osteosynthesis and rigid fixation.

Accuracy of cephalometric and video imaging program Dentofacial Planner Plus in orthognathic surgical planning.

The prediction of profile changes after surgery poses a problem due to the variability of the soft tissue and the differences in soft-tissue translations relative to osseous changes. This study examined the accuracy of computer predictions of such soft-tissue changes. Twenty-five patients with mandibular retrognathia were examined before and after orthognathic surgery. Changes in soft-tissue reference points were correlated to translations of hard-tissue references in the sagittal and vertical planes, and the measurements from these patients were compared to results predicted in preoperative planning by the cephalometric and video imaging program Dentofacial Planner. In surgical treatment involving advancement of the mandible, the mean operative advancement of the osseous pogonion was 6.06 mm. The corresponding movements of soft-tissue references, expressed as percentages relative to the movement of the osseous pogonion in the sagittal plane, were 98.4% for the soft-tissue pogonion, 93.6% for the soft-tissue menton, and 49.0% for the soft-tissue labrale inferior. The same measurements were carried out in the vertical plane and the changes in soft-tissue references were compared to those predicted in preoperative planning using the Dentofacial Planner. The predicted images were perceived as agreeing with the actual image most frequently in the lip and nasal area, while the highest degree of error was seen in the submental region. An overall predictability of more than 80% can be attained by planning mandibular advancement operations for correction of mandibular retrognathia using the Dentofacial Planner.

The accuracy of preoperative orthognathic predictions.

We assessed the accuracy of preoperative OPAL trade mark orthognathic predictions by retrospective analysis of 25 Class II patients who had had orthodontic treatment combined with mandibular advancement osteotomy. Preoperative and postoperative lateral cephalographs were digitised and surgical predictions generated using OPAL software. Each prediction was compared with the corresponding clinical changes. We also made a method error study by doing a random retracing of 25 cephalographs. Predictions of some of the principal OPAL values (SNA, ANB, LAFH%, OJ, OB) were reasonably accurate in terms of mean values. However, there were large individual variations for most variables and predictions of the vertical skeletal, incisor, and Wits measurements were imprecise. In particular, there was a bias towards under-prediction of the vertical skeletal changes when there was more backward mandibular rotation than anticipated. Immediate postoperative cephalographs were also affected by a 2.1mm mean downward displacement of the mandible as a result of the surgical wafer.