An interventional study of Polygraphy and Questionaire in Apnea, Obstructive, sponsored by Ziekenhuis Oost-Limburg. Completed at 1 site in Belgium. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by Ziekenhuis Oost-Limburg · Not applicable, Interventional, and Treatment
The goal of this randomised, controlled cross-over study is to compare two mandibular repositioning devices (MRA) already on the market in the treatment of mild-to-moderate obstructive sleep apnea.
Patiënt will test the first MRA for 3 months, after a wash out period of 2 weeks they will test the second MRA for 3 months. It will be randomised what type of MRA will be tested first and second.
A mandibular repositioning appliance (MRA) is the primary treatment option for patients with mild to moderate obstructive sleep apnea (OSA), as well as for those with severe OSA who are intolerant to continuous positive airway pressure (CPAP) therapy or for whom surgical interventions are not viable. MRAs function by advancing the mandible, thereby increasing the volume of the upper airway and reducing its tendency to collapse during sleep. Various types of MRAs are available, and multiple classification systems can be employed to distinguish between these different types.
Mandibular repositioning appliances (MRAs) can be either custom-made or universal. Custom-made devices, which are typically more expensive, are fabricated in a dental laboratory using dental impressions. In contrast, prefabricated devices, often thermoplastic MRAs, are generally less costly and readily available over the counter.
Mandibular repositioning appliances (MRAs) can be classified as non-titratable, also known as monoblock devices, which have a fixed position, or titratable devices, which allow for gradual adjustment of the mandibular position until the desired therapeutic effect is achieved. Current guidelines recommend the use of titratable MRAs.
Titratable mandibular repositioning appliances (MRAs) can be further categorized into two types: midline traction devices, where the upper and lower components are connected at the front of the device, and bilateral thrust devices, where the upper and lower components are linked in the lateral or (pre-)molar regions.
Within the latter category, various designs exist, including devices that are adjustable on both sides using Hyrax screws and 3D-printed devices equipped with a series of lower components that allow for adjustments in mandibular position.
An example of an MRA adjustable with Hyrax screws is the SomnoDent® device (SomnoMed, Denton, Texas, USA). An example of a device utilizing a series of lower components for titration is the OrthoApnea appliance (ORTHOAPNEA S.L., Málaga, Spain), which features a specific attachment mechanism.
Although studies have already been published comparing different types of "bilateral thrust" devices, no studies to date have directly compared the categories mentioned above. The hypothesis of the investigators is that both appliances have similar effectiveness in the treatment of mild-to-moderate obstructive sleep apnea.
Primary objective:
Improvement of AHI, measured by polygraphy before treatment and after treatment with each MRA.
Secondary objective;
Peripheral oxygen saturation, measured by polygraphy before treatment and after treatment with each MRA
Endpoints:
The investigators assess the objective improvement in OSA by comparing polygraphy results taken before and after treatment with each MRA. To evaluate the subjective effects of the MRA, the investigators compare the scores from the Epworth Sleepiness Scale. The participants subjective experience with each MRA type is measured using a patient experience questionnaire, along with noting the final preference for device type of the participants.
Study design:
Inclusion criteria:
In order to be eligible to participate in this study, a subject must meet all of the following criteria:
Exclusion criteria:
A potential subject who meets any of the following criteria will be excluded from participation in this study:
2,198 studies on the registry are indexed under Sleep Apnea, Obstructive; 469 are open to participants now.
This study's enrollment of 16 is below the median of 53 across 1,448 interventional studies indexed under Sleep Apnea, Obstructive.
Browse Sleep Apnea, Obstructive studies →Ziekenhuis Oost-Limburg is the lead sponsor of 66 studies on the registry; 17 are open to participants now.
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In order to be eligible to participate in this study, a subject must meet all of the following criteria:
A potential subject who meets any of the following criteria will be excluded from participation in this study:
Use of MRA device 1 for 3 months, use of MRA device 2 for 3 months
Diagnostic Test: Polygraphy · Other: Questionaire · Other: Question
Use of MRA device 2 for 3 months, use of MRA device 1 for 3 months
Diagnostic Test: Polygraphy · Other: Questionaire · Other: Question
Polygraphy after 3 months of use of each appliance: an unattended home sleep study at the end of the first treatment period, and in-hospital polygraphy at the end of the second treatment period.
Epworth Sleepiness Scale o Johns, Murray W. "A New Method for Measuring Daytime Sleepiness: The Epworth Sleepiness Scale." Sleep, vol. 14, no. 6, 1991, pp. 540-545.
Patient experience questionnaire o Ng, E.T., Perez-Garcia, A., en Lagravère-Vich, M.O. "Development and Initial Validation of a Questionnaire to Measure Patient Experience with Oral Appliance Therapy." Journal of Clinical Sleep Medicine, vol. 19, nr. 8, 1 aug. 2023, pp. 1437-1445. doi: 10.5664/jcsm.10562. PMID: 37082817; PMCID: PMC10394373
Patient final choice of preferred MRA
AHI
Improvement of AHI (apnea-hypopnea index), measured by polygraphy before treatment and after treatment with each MRA. The goal of the mandibular advancement device is to reduce the number of apneas and hypopneas per hour, apneas are periods when a person stops breathing and hypopneas are instances where airflow is blocked, causing shallow breathing. This is measured by a polygraphy-test overnight at the patiënts home.
Time frame: 3 monthts after use of first MRA (mandibular advancement device), 3 months after use of second MRA (mandibular advancement device)
Peripheral oxygen saturation 1
Measured by polygraphy * Average saturation (measured in %) * Lowest saturation (measured in %) Oxygen saturation in percent is the fraction of oxygen-saturated haemoglobin relative to total haemoglobin (unsaturated + saturated) in the blood \* 100%
Time frame: 3 monthts after use of first MRA, 3 months after use of second MRA
Peripheral oxygen saturation 2
Measured by polygraphy o Oxygen desaturation index \>3% (events/h) Desaturation episodes are defined as a decrease in the mean oxygen saturation of ≥3% for more than 10 seconds per hour
Time frame: 3 monthts after use of first MRA, 3 months after use of second MRA
Peripheral oxygen saturation 3
Measured by polygraphy o Total duration with saturation \< 90% The percentage of cumulative time with oxygen saturation below 90% in total sleep time.
Time frame: 3 monthts after use of first MRA, 3 months after use of second MRA
ESS
Epworth Sleepiness Scale (questionaire) The minimum value is 0 and the maximum value is 24. A higher score means a worse outcome, indicating more excessive daytime sleepiness. The Epworth Sleepiness Scale is scored by adding up the individual scores for each of the eight questions. Each question is rated on a scale of 0 to 3, with 0 being "no chance of dozing" and 3 being "high chance of dozing." ter daytime sleepiness. Score range Interpretation 0-5 Lower normal daytime sleepiness 6-10 Normal daytime sleepiness 11-12 Mild excessive daytime sleepiness 13-15 Moderate excessive daytime sleepiness 16-24 Severe excessive daytime sleepiness
Time frame: 3 monthts after use of first MRA, 3 months after use of second MRA
Patient experience questionnaire
Patient experience with each appliance, assessed after 3 months of use. The appliance-design domain of the Oral Appliance Therapy Patient Experience Questionnaire (OATPEQ; Ng et al., J Clin Sleep Med 2023) was used, translated into Dutch. It comprises 13 statements, each scored from 0 to 4, giving a total score ranging from 0 to 52. A higher score indicates a more positive patient experience.
Time frame: 3 months after use of the first MRA, 3 months after use of the second MRA
Final choice
Patient final choice of preferred MRA. At the final visit, after using each MRA (type 1 and type 2) for three months (with a two-week washout period in between), the patient will choose their preferred device. The final choice will be noted down after oral questioning.
Time frame: after the use of each MRA for 3 months
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Ziekenhuis Oost-Limburg