Sleep Scientists Push for Smarter Ways to Measure Oral Appliance Use in Sleep Apnea Therapy

Obstructive sleep apnea affects hundreds of millions of people worldwide, fragmenting their sleep, starving their tissues of oxygen and raising the long-term risk of cardiovascular disease, stroke and cognitive decline. While continuous positive airway pressure, or CPAP, remains the best-studied first-line treatment, a quieter rival has been gaining ground in sleep clinics: the mandibular advancement device, a custom-fitted oral appliance that holds the lower jaw forward during sleep to keep the upper airway open. Yet a persistent problem shadows this therapy, and it is the focus of a new letter published in the Journal of Clinical Sleep Medicine. Clinicians still do not have a reliable, standardized way of knowing whether patients are actually wearing their devices night after night.

The letter, written by Nashmia Faraz, Haider Imran and Abdul Basit of the Department of Medicine at Foundation University Medical College in Islamabad, Pakistan, takes aim at the gap between objective and subjective measures of adherence in oral appliance therapy. Published in September 2026, the correspondence responds to emerging longitudinal evidence on how adults with obstructive sleep apnea actually use their appliances over a full year, and it argues that the field must refine how adherence is defined, measured and interpreted before the therapy’s real-world effectiveness can be judged fairly.

The concern is not academic hair-splitting. An oral appliance that sits in a drawer delivers no therapeutic benefit, no matter how well it was designed or how effectively it advanced the jaw in a laboratory titration study. Adherence is the hinge on which the entire treatment turns. For CPAP, this lesson was learned early and painfully: studies famously showed that early patterns of use in the first days and weeks strongly predicted long-term adherence, prompting sleep medicine to invest heavily in objective compliance monitoring, telehealth coaching and early intervention programs. Modern CPAP machines log every hour of use, and those data streams are now woven into routine care. Oral appliance therapy, by contrast, has largely depended on what patients report at follow-up visits.

Self-report is a notoriously fragile foundation for clinical decisions. Patients may genuinely believe they wear their devices more than they do, because nights of fragmented sleep blur memory and because social desirability nudges people toward the answers they think their clinicians want to hear. The literature cited in the letter makes the scale of the discrepancy unmistakable. A landmark 2013 study published in Chest by Dieltjens and colleagues compared objectively measured compliance, captured by embedded microsensors, with self-reported compliance among patients using mandibular advancement devices for sleep-disordered breathing. The objective data revealed substantially lower usage than patients reported, exposing a gap large enough to distort outcome studies, cost-effectiveness analyses and clinical audit alike.

Embedded microsensors have since become the technical benchmark for objective adherence measurement in oral appliance therapy. These tiny temperature-sensitive chips sit inside the appliance and register when the device is actually in the mouth, distinguishing genuine use from mere possession. When the appliance is inserted, oral temperature triggers the sensor; when it rests on a bedside table, no temperature change is recorded. The approach mirrors the objective compliance chips that transformed CPAP monitoring, and it offers sleep medicine something it has long lacked for dental devices: a truthful, time-stamped record of real-world use patterns, including how many nights per week the appliance is worn and for how many hours per night.

The new longitudinal pilot data that prompted the letter tracked both objective and subjective adherence in adults with obstructive sleep apnea over one year, providing a rare window into how usage evolves well beyond the initial adaptation period. The corresponding letter argues that such data should push the field toward a more nuanced adherence framework, one that distinguishes between objective device use, patient-perceived use and clinical response, rather than collapsing them into a single self-reported figure. The authors, who conceptualized and drafted the correspondence with no external funding and no competing interests, position their contribution as a call to tighten the methodological standards of oral appliance research.

Why does this refinement matter now? Oral appliance therapy is expanding rapidly. Clinical guidelines recommend it for patients with mild to moderate obstructive sleep apnea and for those with severe disease who cannot tolerate or decline CPAP. Dental sleep medicine has grown into a distinct subspecialty, and the global market for mandibular advancement devices continues to climb as obesity rates and disease prevalence rise. Every prescription implicitly assumes that the device will be worn consistently. If adherence measurement lags behind prescription volume, the field risks both overtreatment, with devices dispensed to patients who will never use them, and undertreatment, with genuine adherence problems overlooked until symptoms return or cardiovascular risk quietly accumulates.

The letter also draws an instructive parallel with the CPAP literature, including the 2007 study by Budhiraja and colleagues in the journal Sleep demonstrating that early CPAP use identified subsequent long-term adherence. That finding reshaped clinical practice, motivating early follow-up and, eventually, remote monitoring programs that flag struggling patients within days. For oral appliances, the analogous evidence base is younger and thinner, but studies such as the 2022 investigation by Kwon and colleagues in the Journal of Sleep Research show that remote monitoring and structured feedback can measurably improve objective compliance with mandibular advancement devices. Together, these strands of evidence suggest that objective adherence measurement is not merely a research nicety; it is the enabling technology for the same kind of proactive, data-driven care that rescued CPAP adherence a generation ago.

The technical challenges, however, are real. Microsensor data must be validated against true wear events, sensors can fail or be damaged during cleaning, and different sensor generations may not produce comparable metrics. The field lacks universally accepted adherence thresholds for oral appliances, whereas CPAP benefited from widely used conventions such as the Medicare definition of four hours per night on seventy percent of nights, itself a contested standard. Without consensus definitions, meta-analyses of appliance effectiveness will continue to mix studies whose adherence figures mean different things, blurring genuine differences in therapeutic efficacy with differences in measurement practice. The authors of the letter imply that resolving this definitional tangle is a prerequisite for the next generation of oral appliance research.

What would refined adherence assessment look like in practice? The ingredients are already on the table: objective sensor-derived metrics reporting nights and hours of use, patient-reported measures captured with validated questionnaires, and clinical outcomes such as the apnea-hypopnea index on follow-up polysomnography or home testing. Longitudinal designs, like the one-year pilot study that sparked the correspondence, add the crucial temporal dimension, revealing whether adherence decays over months and which patients are at greatest risk of abandoning therapy. Integrating these data streams into electronic health records and telemedicine platforms could finally give dental sleep medicine the feedback loops that clinicians need, allowing early, targeted interventions before non-adherence becomes entrenched. As oral appliance therapy takes its place alongside CPAP in mainstream sleep medicine, the message from Islamabad is clear: the therapy can only be as good as the evidence that patients are actually using it, and measuring that use honestly is the field’s next essential task.

Subject of Research: Objective versus subjective adherence assessment in oral appliance therapy for obstructive sleep apnea

Article Title: Refining adherence assessment in oral appliance therapy for obstructive sleep apnea

Article References: Faraz, N., Imran, H., & Basit, A. (2026). Refining adherence assessment in oral appliance therapy for obstructive sleep apnea. Journal of Clinical Sleep Medicine, 22(1), Article 158. https://doi.org/10.1007/s44470-026-00176-7

Image Credits: AI Generated

DOI: 10.1007/s44470-026-00176-7

Keywords: obstructive sleep apnea, oral appliance therapy, mandibular advancement device, adherence measurement, microsensors, CPAP, sleep medicine, self-reported compliance, remote monitoring, dental sleep medicine, Journal of Clinical Sleep Medicine, Refining