Mandibular advancement device matches CPAP on blood pressure in sleep apnea trial
Continuous positive airway pressure has long been the default treatment for sleep apnea, especially when hypertension is part of the picture. A new randomized study adds a practical wrinkle: a custom mandibular advancement device, or MAD, lowered blood pressure about as much as CPAP over 12 months in adults at elevated cardiovascular risk. The trial enrolled 180 people, 85% of them men, all with moderate or severe sleep apnea and high blood pressure. Participants were randomly assigned to CPAP or MAD, and both groups improved in clinically meaningful ways that matter at the bedside.
The blood pressure effect was modest in absolute terms, but the comparison between devices is the real story. Average reductions were 1 point in the CPAP group and 2.3 points in the MAD group. In a disorder tied to sympathetic activation, nocturnal hypoxemia, and persistent vascular stress, even small shifts can matter when they accumulate over time. Sleep apnea does not just fragment sleep; it keeps the cardiovascular system under near-constant strain, and therapy is aimed at breaking that cycle.
One sentence captures the practical tension in this field: CPAP remains the standard, yet many patients never adapt to it.
Why a dental appliance can plausibly lower cardiovascular stress
CPAP works by delivering pressurized air through a mask to hold the airway open during sleep. The physiology is direct and familiar, but the burden of nightly mask use, pressure sensation, and nasal or oral discomfort often limits real-world adherence. MAD works differently. The device fits over the teeth and repositions the jaw, and in some designs the tongue, to keep the upper airway from collapsing. By reducing airway obstruction, it can lessen the repetitive arousals and oxygen desaturations that drive blood pressure elevation overnight and during the day.
That mechanism helps explain why the two arms could converge on similar blood pressure results even if the devices are not identical in design or reputation. The MAD group used the device a median of 5.5 hours per night, compared with 4.9 hours for the CPAP group. Adherence is not a side issue here; it is part of the treatment itself. A therapy that patients actually wear may outperform a more effective device that sits unused on the nightstand.
Daytime sleepiness improved in both arms
Both groups reported less excessive daytime sleepiness, a core symptom of sleep apnea and a major driver of poor function, impaired attention, and lower quality of life. The study also found that unplanned hospitalizations declined in both groups after the first six months. The report does not isolate the reasons for those hospitalizations, so the finding should be interpreted cautiously, but it fits the broader expectation that better nocturnal breathing can translate into fewer acute clinical disruptions.
Side effects differed in a way clinicians will recognize immediately. The MAD group most often struggled with jaw pain and tooth discomfort. The CPAP group reported dryness and pain in the nose and mouth. These are not trivial nuisance effects; they often decide whether therapy is continued or abandoned. For a patient who cannot tolerate a mask, jaw discomfort may be a manageable tradeoff. For another patient with dental problems or temporomandibular joint symptoms, the opposite may be true.
What the numbers do and do not establish
The study is small, and that limits how far the findings can be extended. Still, the randomized design and the 12-month follow-up give the comparison weight. The cohort included adults with moderate or severe disease plus hypertension, so the results are most relevant to patients in whom the cardiovascular stakes are already high. The trial does not erase the place of CPAP. It does, however, make a strong case that MAD deserves a more prominent role when CPAP is poorly tolerated or not used as directed.
The blood pressure reductions were modest rather than dramatic, which is exactly what many clinicians see in sleep apnea care: the gains are often incremental, not spectacular. Yet incremental gains can still influence long-term risk when they are sustained and paired with better sleep quality and less nighttime sympathetic surging. The comparison also reflects a broader truth about chronic disease treatment. Device choice is not only about efficacy under ideal conditions; it is about which therapy patients can live with night after night.
Who may benefit most from the dental-device approach
For patients with moderate to severe sleep apnea and high blood pressure, CPAP should still be considered the preferred first-line therapy. The evidence base remains deeper, and the airway-opening effect is immediate and well established. Even so, the study makes room for a more individualized conversation. Patients who cannot tolerate CPAP, struggle with adherence, or repeatedly remove the mask during sleep may have a realistic alternative in a custom MAD.
The decision is likely to hinge on the same factors that shape everyday sleep-medicine practice: comfort, dental status, symptom burden, and willingness to persist with treatment. A device that is slightly less canonical but more wearable may be the one that actually lowers blood pressure over the course of a year. That is not a loophole in treatment; it is a reminder that chronic therapy lives or dies by adherence.
The main caution is straightforward. This was a relatively small study, and the findings should not be overextended to every patient with sleep apnea. Longer and larger comparisons will be needed to determine whether the apparent parity in blood pressure control holds across broader populations and whether the hospitalization signal persists. For now, the trial strengthens the case that oral appliance therapy is more than a fallback option for sleep apnea—it may be a serious cardiovascular strategy for the right patient.