Hawley retainers.
An acrylic baseplate with a labial bow and clasps. It is the oldest removable retainer design in use and it remains the right answer in several specific situations.
What it does that a clear retainer does not
It allows the posterior teeth to settle. Because the occlusal surfaces are not covered, the buccal segments can continue to intercuspate after treatment, which improves the final occlusion in a way a full-coverage appliance prevents.
It is adjustable. The labial bow and clasps can be tightened, loosened or reshaped chairside, and minor tooth movement can be achieved with an active component if a small correction is wanted.
And it is durable. Acrylic and stainless steel tolerate handling that thermoformed material does not, which matters for patients who are hard on appliances.
Where it is less suitable
It is visible, which for some patients is decisive and should be established before it is made rather than after.
It holds rotations less rigidly than a full-coverage appliance. Where a case involved difficult rotations, the labial bow and baseplate do not resist relapse as effectively as a clear retainer engaging every surface.
It also takes up more space lingually, which affects speech initially and is a common early complaint. Most patients adapt within days.
Design decisions
The labial bow and its adjustment loops, the clasp type and which teeth are clasped, the extent of the baseplate, and whether any active component is wanted.
Adams clasps on the first molars are the conventional retention, with variations depending on the dentition available. Where a patient has restorations or implants on the clasped teeth, say so — the undercut available may differ from the natural tooth.
For an upper appliance, the palatal extent affects both retention and speech. State a preference if you have one.
Records
An accurate impression or scan of the arch capturing full clinical crowns, the sulcus and the palate for an upper appliance. The opposing arch and a bite record where the occlusion matters to the design.
Take the record immediately after appliance removal. Teeth move quickly at that point and a delayed record produces a retainer that does not seat.
Where a bonded retainer is being placed at the same time, capture it or note its position so the baseplate can accommodate it.
Delivery and adjustment
Expect to adjust at fit. The appliance should seat fully without rocking, the clasps should engage without being tight enough to be difficult to remove, and the labial bow should contact lightly rather than actively.
Check that the baseplate does not impinge on the tissue anywhere, and polish anywhere you have adjusted. Rough acrylic against the palate is a common reason a retainer stays in a drawer.
Give the patient written care instructions. See appliance care.
Active components
A Hawley can carry a small active element — a finger spring, a modified labial bow — where a minor correction is wanted rather than pure retention.
That is a different appliance in intent, and it needs stating explicitly. An appliance built as a passive retainer will not deliver movement, and one built with an active component and prescribed as a retainer will move teeth nobody intended to move.
Say what movement you want, how much, and over what period. Where the correction is more than minor, the case is orthodontic treatment rather than retention.
What to put on the prescription
Hawley retainer, the arch, the clasp design and which teeth to clasp, the labial bow design, and any active component wanted.
Note whether posterior settling is intended, and whether the patient has any restorations or bonded retainers the appliance must work around.
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