Sleep appliances.
Mandibular advancement appliances hold the lower jaw forward during sleep, opening the airway. They have a genuine role, and they sit within a medical diagnosis rather than replacing one.
Diagnosis comes first
Snoring and obstructive sleep apnoea are not the same thing, and the difference matters medically. Untreated obstructive sleep apnoea carries cardiovascular and neurocognitive consequences, and it is diagnosed by sleep study rather than by history or appearance.
A dental appliance provided for undiagnosed snoring may relieve the noise while leaving significant apnoea untreated, and the patient's partner stops reporting the symptom that would otherwise have led to diagnosis.
Where sleep-disordered breathing is suspected, refer for assessment. Appliance therapy for diagnosed apnoea belongs within a medically supervised plan, in collaboration with the physician managing the patient.
How they work
The appliance holds the mandible in a protruded position, which advances the tongue and soft palate and increases the dimension of the upper airway.
EMA and comparable designs use interchangeable elastic straps or connectors between upper and lower components, allowing the degree of advancement to be adjusted after fitting rather than fixed at fabrication.
That adjustability is important, because the effective position is found by titration over weeks rather than predicted at the outset.
Recording the protrusive position
The construction bite is the critical record. It sets the starting position, typically a proportion of the patient's maximum protrusion rather than the maximum itself, with the vertical opening kept as small as the design allows.
A protrusive gauge makes this reproducible and is worth using. Recording by eye produces a starting position that is either ineffective or immediately uncomfortable.
State the protrusion recorded and the vertical opening on the prescription. The laboratory cannot infer either from the casts.
Side effects to discuss beforehand
Morning jaw discomfort and transient occlusal changes are common early and usually settle. Long-term wear can produce genuine occlusal change — posterior open bite, anterior movement — which is progressive and not always reversible.
Temporomandibular symptoms can be provoked in susceptible patients, and excessive salivation or dryness is common initially.
These should be explained before treatment and monitored at review. A morning repositioning exercise and regular occlusal checks are part of ordinary management rather than a response to a problem.
Records
Accurate impressions or scans of both arches capturing full clinical crowns and adequate undercut for retention, plus the construction bite in the recorded protrusive position.
Retention matters more here than in most appliances — the device has to hold the mandible forward against muscle activity all night. A record that does not capture the undercuts produces an appliance that dislodges.
Follow-up and titration
The starting protrusive position is a starting point. Effective advancement is found by titration over weeks, guided by the patient's and partner's reports and, where apnoea is diagnosed, by objective reassessment.
Adjustable designs allow this without remaking the appliance, which is the principal reason to prefer them over a fixed-position device.
Where the appliance is being used for diagnosed apnoea, follow-up sleep testing with the appliance in place is the responsibility of the managing physician and should be arranged rather than assumed.
What to put on the prescription
Note the appliance type under Special Instructions, state the protrusive position recorded and the vertical opening, and confirm the construction bite is included.
Note existing restorations, implants or missing teeth affecting retention, and any known temporomandibular history.
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