Fixed retainers: cost, pros and cons, and what to do when one breaks

A fixed retainer (also called a permanent or bonded retainer) is a thin wire bonded to the back of your front teeth to stop them moving after braces or Invisalign. At Toothi London a fixed wire retainer is £250 per arch, and one is included in every Invisalign package.

“Permanent” is a slightly generous name. A fixed retainer stays in for years, often many, but the bond on one tooth can come loose and the wire itself can bend or snap. This page explains what a fixed retainer is, who it suits, what it costs, how to keep it clean, and what to do when it fails — which it will, eventually, for most people.

The wire is shaped to the inside of your front teeth, most often the lower canine to canine, sometimes the upper too, and bonded to each tooth with a small amount of tooth-coloured composite. It sits on the tongue side, so it is not visible from the front and does not affect your smile. Because it is always in place, it holds the teeth that are most prone to relapse — the lower front teeth — without relying on you to remember a removable retainer every night.

Fitting takes one short appointment and needs no injections: the enamel is cleaned and prepared, the wire is positioned, and the composite is set with a light. It feels strange to the tongue for a few days and then you forget it is there.

For most adults after Invisalign the best arrangement is both: a fixed wire on the lower front teeth and a clear removable retainer over the top at night. The fixed wire covers the teeth most likely to move; the clear retainer covers everything else and acts as a backup if a section of wire comes loose.

Prices are fixed and taken from our fees page. If a section of an existing fixed retainer has come loose, we look at it first and tell you whether it can be re-bonded or needs replacing before anything is done.

• ✓  Do not leave it. A loose end can scratch your tongue, and the tooth it has come off will start to move within weeks. Book an appointment as soon as you notice.
• ✓  Wear your removable retainer every night in the meantime if you have one. If it no longer fits, say so when you book and we will scan you for a new one at the same visit.
• ✓  Do not try to glue it or pull it off. Superglue is not safe in the mouth and pulling can take enamel with it. If a sharp end is bothering you, a little orthodontic wax over it will keep you comfortable until your appointment.
• ✓  Bring the wire if it has come off completely. Sometimes it can be re-bonded; if not, a replacement is £250.

The wire creates small spaces where plaque and tartar build up, and over time that is what causes gum inflammation and staining around the lower front teeth. Three habits keep it in check:

• ✓  Interdental brushes or a floss threader once a day, passing under the wire between each pair of teeth.
• ✓  Angle your toothbrush down behind the lower front teeth so the bristles reach the wire, not just the tooth surface above it.
• ✓  Regular hygiene appointments. Tartar behind a fixed retainer is almost impossible to remove at home; our hygiene appointments include a careful clean around the wire, and your hygienist will check the bond on each tooth while they are there.