ANSWERS

How do I know if my mandibular advancement device fits?

A properly fitted mandibular advancement device seats fully on both arches without rocking, stays in place through the night, and advances the mandible 60 to 70 percent of maximum protrusion without jaw pain lasting beyond 30 minutes after removal.

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Why it works this way

Seating and retention checks

A mandibular advancement device (MAD) should snap onto both the upper and lower arches with even pressure across every tooth. Run your tongue along the inside edge; if you feel gaps between the appliance and the lingual surfaces, the impression or scan that built the device was off. The American Academy of Dental Sleep Medicine (AADSM) practice parameters call for full occlusal coverage with no rocking when you press alternately on the left and right sides. If the device pops loose during the night and you wake with it on the pillow, retention has failed and the lab needs to adjust or remake.

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How long does it take to adjust to a new mandibular advancement device?

Most patients adapt within 2 to 4 weeks. The first week typically involves increased salivation, mild jaw stiffness in the morning, and tooth pressure that fades within 30 minutes of removal. By week three, the appliance should feel routine to insert and the morning bite should return to baseline within an hour. If symptoms persist past 30 days, the prescribing dentist should re-evaluate fit, advancement position, and whether a morning repositioner is needed.

What is the difference between a dorsal-fin and a Herbst-style MAD?

Dorsal-fin appliances use angled acrylic fins on the upper and lower trays that engage when the mandible drops back, holding the jaw forward. Herbst-style devices use bilateral telescopic arms with advancement screws for calibrated titration. Dorsal-fin designs allow more lateral movement and are often preferred for bruxism cases. Herbst designs give the prescribing dentist precise control over advancement increments. Dani Dental fabricates both, with the choice driven by the dentist's case plan and the patient's mandibular range of motion.

Can a mandibular advancement device change my bite permanently?

Long-term MAD use can cause minor occlusal changes, most commonly posterior open bite or anterior crowding, in roughly 10 to 15 percent of patients per published longitudinal studies. Morning repositioners and consistent follow-up appointments at 6 and 12 months reduce the risk. The prescribing dentist should document baseline occlusion with photos and a study model or scan before delivery, then compare at each recall. If changes appear, advancement is reduced or the appliance design is modified before the shift becomes permanent.

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