Marc J. Braem

Objective measurement of compliance during oral appliance therapy for sleep-disordered breathing

Background Oral appliance (OA) therapy is increasingly prescribed as a non-continuous positive airway pressure treatment modality for sleep-disordered breathing (SDB). Although OA therapy is reported to be efficacious for the treatment of SDB, data on compliance remain limited to self-report. Methods In this 3-month prospective clinical trial, the main outcome was to assess the safety and feasibility of an objective measurement of compliance during OA therapy using an embedded microsensor thermometer with on-chip integrated readout electronics in 51 consecutive patients with an established diagnosis of SDB (AHI 18.0±11.9/h; age 47±10 y; BMI 26.6±4.0 kg/m2; men/women: 31/20). Patients were unaware of the purpose of the study. Results No microsensor-related adverse events were recorded. In addition, no problems were encountered during the readout of the compliance data. Out of 51 microsensors, one had a technical defect and was lost to follow-up. In this study, the overall objective mean rate of OA use was 6.6±1.3 h per day with a regular OA users’ rate of 82% at the 3-month follow-up. Statistical analysis revealed no significant differences between objective and self-reported OA compliance data in this study. Measurement of the objective OA compliance allowed us to calculate the mean disease alleviation (MDA) as the product of objective compliance and therapeutic efficacy. MDA serves as a measure of the overall therapeutic effectiveness, and turned out to be 51.1%. Conclusions The results illustrate the safety and feasibility of objective measurement of OA compliance. The objective measurement of OA compliance allows for calculation of the MDA.

Drug‐induced sleep endoscopy in sleep‐disordered breathing: Report on 1,249 cases

To describe upper airway (UA) collapse patterns during drug‐induced sleep endoscopy (DISE) in a large cohort of patients with sleep‐disordered breathing (SDB) and to assess associations with anthropometric and polysomnographic parameters.

In vitro fatigue behavior of restorative composites and glass ionomers

OBJECTIVES This in vitro study was conducted to investigate the fatigue behavior of several dental restoratives, including composites, glass ionomers and a resin-reinforced glass ionomer. METHODS Fatigue was imposed under a reverse stress-controlled regimen, following a staircase approach. Samples were stored and tested under both dry and wet conditions. The following parameters were measured and analyzed: Youngs modulus, restrained fracture strength, and flexural fatigue limit. RESULTS As a general trend, all products showed a decrease in Youngs modulus following water sorption. For all products except the resin-reinforced glass ionomer, the same trend was seen in the restrained fracture strength. This is, however, no longer valid for the flexural fatigue limit: the trend is steady-state for the glass ionomers, status quo for the resin-reinforced glass ionomer, and all composites tested show a decrease. SIGNIFICANCE The diversity in structure of both composites and glass ionomers does not allow findings for one product to be extrapolated to other similar products.

Sleep endoscopy with simulation bite for prediction of oral appliance treatment outcome

The aim of this study was to assess the value of drug‐induced sleep endoscopy (DISE) using a custom‐made simulation bite in maximal comfortable protrusion (MCP) of the mandible, in the prediction of treatment outcome for obstructive sleep apnea (OSA) with a mandibular advancement device (MAD). Two hundred patients (74% male; age 46 ± 9 years; apnea–hypopnea index [AHI] 19 ± 13 h−1 sleep; body mass index [BMI] 27 ± 4 kg m−2) with sleep‐disordered breathing underwent DISE with a simulation bite in MCP. One hundred and thirty‐five patients with an established diagnosis of OSA commenced MAD treatment. The associations between the findings during DISE with simulation bite and treatment outcome were evaluated. Treatment response was defined as a reduction in AHI following MAD treatment of ≥ 50% compared to baseline. Overall MAD treatment response in the studied population was 69%. The results of this study demonstrated a statistically significant association between a positive effect of the simulation bite on the upper airway patency during DISE and treatment response with MAD (P < 0.01). The results of this study suggest that the use of a simulation bite in maximal comfortable protrusion (MCP) of the mandible, as used during DISE in patients with OSA, tends to be effective in predicting treatment response of MAD treatment.

A promising concept of combination therapy for positional obstructive sleep apnea

PurposeThe objective of this randomized controlled trial was to assess the additional effect of a chest-worn sleep position trainer (SPT) in patients with residual supine-dependent obstructive sleep apnea (sdOSA) under mandibular advancement device (MAD) therapy.MethodsBaseline and follow-up polysomnography with MAD were performed. Twenty patients with sdOSA under MAD therapy underwent two consecutive randomized polysomnographies: one with SPT and one with combination of SPT + MAD. Data are presented as median (quartile 1, quartile 3).ResultsThe SPT reduced the time spent in supine sleeping position compared to baseline and MAD therapy. Both MAD and SPT were individually effective in reducing the overall apnea/hypopnea index (AHI) significantly when compared to baseline from 20.8 (15.1; 33.6)/h at baseline to 11.0 (6.7; 13.8)/h and to 11.1 (3.5; 17.7)/h with MAD or SPT, respectively. The combination of SPT + MAD further reduced the overall AHI to 5.7 (3.6; 7.4), which was significantly lower than with MAD alone (p < 0.001) and SPT alone (p < 0.008), respectively.ConclusionsThe results of this study indicate that combination of SPT + MAD leads to a higher therapeutic efficacy in patients with sdOSA under MAD therapy when compared to one of the treatment modalities alone.

Objectively measured vs. self-reported compliance during oral appliance therapy for sleep-disordered breathing

BACKGROUND Assessment of the overall therapeutic effectiveness of oral appliance therapy can only be realized through objectively measured compliance. The aims of this study were to assess objectively measured compliance during oral appliance therapy at 1-year follow-up and to compare these data with self-reported use. METHODS Fifty-one eligible patients were enrolled in this 1-year prospective clinical study (men, 61%; mean age, 49 ± 10 years; apnea-hypopnea index, 18.0 ± 11.9 events/h sleep; BMI, 26.6 ± 4.1 kg/m²). Objective compliance during oral appliance therapy at 1-year follow-up was assessed with a microsensor thermometer. Subjective compliance was assessed by self-report. Patients with a mean objectively measured use of ≥ 4 h/night on 70% of nights monitored were considered regular users. The mean disease alleviation was calculated as a measure of overall therapeutic effectiveness. RESULTS High agreement between objective and subjective compliance data at 1-year follow-up was reported (intraclass correlation coefficient, 0.8; 95% CI, 0.5-0.9), showing a mean subjective overestimation of 30 min (95% CI, -3.1 to 1.9; P = .02). The discontinuation rate at 1-year follow-up was 9.8%. The objective mean use rate was 6.4 ± 1.7 h/night at 1-year follow-up in continuing users, with a regular use rate of 83%. The mean disease alleviation was 54.9%. CONCLUSIONS This study is the first to our knowledge to report the 1-year results of objectively measured compliance during oral appliance therapy. In addition, a high agreement between objective and subjective compliance data were reported, with a mean subjective overestimation of 30 min. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT01284881; URL: www.clinicaltrials.gov.

Current opinions and clinical practice in the titration of oral appliances in the treatment of sleep-disordered breathing

Obstructive sleep apnea is characterized by recurrent obstruction of the upper airway during sleep, resulting in episodic reductions in blood oxygen saturation and arousals from sleep. Mandibular repositioning appliances (MRAs) which are worn intra-orally at night, mechanically advance the mandible to help maintain a patent oropharygeal airway and have been proven to be an effective alternative for continuous positive airway pressure in the treatment of obstructive sleep apnea. Titratable MRAs are designed to gradually protrude the mandible applying an easy-to-use mechanical advancing mechanism, until a protrusive position with positive effect on sleep apnea is reached. Considering the relatively low-tech approach of the basic advancement mechanism, the interest in the mechanistic element of the dental treatment of obstructive sleep apnea has increased. The present paper provides an overview of the different titration protocols described in the recent literature together with a discussion of both the clinical and mechanical aspects of treatment. At present, a consensus exists that an optimal titration protocol is of primary importance to achieve a successful treatment outcome with an MRA. To date however, there is no consensus on how to define the optimal titration protocol.

Effects of vertical opening on pharyngeal dimensions in patients with obstructive sleep apnoea

BACKGROUND It is still subject to controversy if an increased vertical opening (VO) is beneficial in oral appliance therapy for the treatment of obstructive sleep apnoea. Each oral appliance has a given thickness causing VO. Therefore, evaluation of the effects of the amount of VO on pharyngeal dimensions is mandatory. METHODS The effects of VO on the cross-sectional area of the upper airway at the level of the tongue base during sleep endoscopy were scored and categorised. RESULTS The figures demonstrate the possible effects of VO on pharyngeal collapse relative to the baseline cross-sectional area and the maximal comfortable protrusion of the mandible. Thirty-two patients (80%) showed an adverse effect of VO (Fig. 1), one patient (2.5%) had a positive effect (Fig. 2), and seven patients (17.5%) demonstrated an indifferent effect (Fig. 3). CONCLUSION Based on literature, the effect of VO on pharyngeal collapse is unclear and the therapeutic impact of VO is not determined. The results of the present study indicate that the effect of VO on the degree of pharyngeal collapse as assessed during sleep endoscopy tends to be adverse, causing an increase in collapsibility in the majority of patients.

Pilot Study of a Novel Mandibular Advancement Device for the Control of Snoring

Objective Mandibular advancement devices (MADs) have been introduced as a conservative, non-invasive treatment for socially disturbing snoring and mild obstructive sleep apnea (OSA). A prospective, non-randomized pilot study was conducted to investigate the efficacy, feasibility, side-effects and compliance of Somnoguard®, an immediately intraorally adaptable MAD made from thermoplastic material. Material and Methods Twenty consecutive heavy snorers with a respiratory disturbance index of <20 events/h were prospectively selected. Prior to the adaptation of the appliance, ambulatory polygraphy was carried out without a MAD. After a 1-month habituation period, a polygraphic evaluation was carried out with the device. Treatment success was defined as a reduction in the apnea–hypopnea index (AHI) of at least 50%. Results The results indicated a success rate of 65%. The AHI decreased from 8.4±2.9 events/h at baseline to 3.9±1.8 events/h with the device (p=0.001). At 1-month follow-up, significant reductions in the snoring index (p<0.001) and the Epworth Sleepiness Scale (ESS) score (p=0.036) were noted. At 6-month follow-up, similar results were achieved, with significant drops in the snoring index (p=0.025) and ESS score (p=0.033). Conclusion We conclude that immediate intraoral adaptation of a low-cost fabricated “one-size-only” MAD is a feasible and well-tolerated treatment for snoring and mild OSA. Further research is needed to evaluate this thermoplastic appliance as a strategy to “screen” the efficacy of MAD treatment in the individual patient with a less expensive appliance before constructing a more expensive custom-made MAD.

Comparison of Two Percutaneous Volar Approaches for Screw Fixation of Scaphoid Waist Fractures Radiographic and Biomechanical Study of an Osteotomy-Simulated Model

BACKGROUND When a surgeon uses a percutaneous volar approach to treat scaphoid waist fractures, central screw placement is complicated by the shape of the scaphoid and by obstruction by the trapezium. In this study, we used radiographs and biomechanical tests to compare the standard volar percutaneous approach with the transtrapezial approach, with regard to central screw placement at the distal pole of the scaphoid. METHODS Fourteen matched pairs of cadaveric wrists were randomly assigned to two treatment groups. Under fluoroscopic control, a guidewire was drilled into the scaphoid, either through a transtrapezial approach or through a standard volar approach that avoided the trapezium. Guidewire position was measured in the coronal and sagittal planes. A transverse osteotomy was performed along the scaphoid waist, and this was followed by the insertion of the longest possible cannulated headless bone screw. Each specimen was placed into a fixture with a pneumatically driven plunger resting on the surface of the distal pole. Load was applied by using a load-controlled test protocol in a hydraulic testing machine. RESULTS All guidewires were inside the central one-third of the proximal pole. The guidewire positions at the distal pole differed significantly between the transtrapezial and standard volar approach groups (p < 0.001). The load to 2 mm of displacement and the load to failure averaged, respectively, 324.4 N (standard error of the mean [SEM] = 73.5 N) and 386.4 N (SEM = 65.6 N) for the transtrapezial approach group compared with 125.7 N (SEM = 22.6 N) (p = 0.002) and 191.4 N (SEM = 36.30 N) (p = 0.005) for the standard volar approach group. CONCLUSIONS The data suggest that, in a cadaveric osteotomy-simulated scaphoid waist fracture model, the transtrapezial approach reliably achieves central positioning of a screw in the proximal and distal poles. This position offers a biomechanical advantage compared with central placement in only the proximal pole.