Last updated: September 2026
Braces come off. Aligners finish. The teeth look straight. And then your dentist hands you a retainer and tells you to wear it. For many patients, this feels like an afterthought, the boring bit after the main event. It is not. Retention is the part that determines whether your straight teeth stay straight or gradually undo the work you just paid for.
Teeth are not set in concrete. They sit in bone, surrounded by gum tissue and held in place by fibres that connect the root to the socket. During orthodontic treatment, those fibres stretch and the bone remodels to accommodate the new tooth position. But after the braces come off, the fibres want to spring back to their original length, and the bone has not fully consolidated around the new position yet.
This tendency to drift back is called relapse, and it is not a failure of the treatment. It is normal biology. Every patient who has had orthodontic work, whether braces or aligners, is susceptible to it. The retainer is the tool that holds the teeth in position while the bone and fibres stabilise, and then long-term to counteract the slow, ongoing tendency of teeth to shift throughout life.
A thin wire is bonded to the back (tongue side) of the front teeth, usually the lower six or the upper six. It is invisible from the outside and works around the clock without any action from you. You cannot forget to wear it because it is permanently attached.
Advantages: no compliance required, always in place, invisible.
Disadvantages: harder to floss (a floss threader or interdental brush is needed to clean under the wire), the adhesive can fail, and if a bond breaks you may not notice immediately. If one tooth detaches from the wire, it can start moving while the others stay put, which can create a new problem. Regular check-ups catch this.
A custom-made clear plastic tray, similar in appearance to a clear aligner, that fits over the teeth. It is worn at night (and initially full-time during the day as well). Patients who have just finished aligner treatment are already familiar with the feel.
Advantages: easy to clean, easy to brush and floss the teeth normally, can be replaced if lost or damaged.
Disadvantages: compliance-dependent (it only works if you wear it), can be lost or forgotten when travelling, wears out over time and needs replacing every one to two years.
An acrylic plate with a wire that sits across the front of the teeth. Less commonly used now than the clear tray type, but still appropriate in some cases, particularly for younger patients.
It depends on the case. Many patients receive a combination: a fixed wire on the lower front teeth (where relapse is most common and most noticeable) and a removable clear tray for the upper arch. Your dentist will recommend the type that suits your specific teeth, your bite, and your ability to maintain it.
This is the part that surprises people. The answer, in practice, is indefinitely.
Full-time wear for removable retainers: in your mouth all day and all night, removed only for eating and cleaning. This is the period when the bone and fibres around the teeth are most actively remodelling and the risk of relapse is highest.
Your dentist may step you down to night-time wear only, provided the teeth are stable at your check-up. The retainer goes in before bed and comes out in the morning.
Most orthodontists recommend continuing night-time wear at least several nights per week for the foreseeable future. Some recommend every night. The bottom line is that teeth move throughout life, slowly, and the retainer is what prevents that movement from undoing the orthodontic result.
A fixed wire, if it stays bonded and intact, provides this retention without you having to think about it. A removable retainer only works when it is in your mouth.
The lower front teeth are the most common site of relapse. They crowd back together, overlapping and rotating, sometimes within months of the retainer being abandoned. Upper teeth can space out again, particularly if there were gaps closed during treatment.
By the time the shift is visible to the patient, the old retainer often no longer fits. At that point, the options are a new course of orthodontic treatment (usually aligners for a relapse case, which is typically shorter than the original treatment) or accepting the new position. Neither is ideal, and both are avoidable by wearing the retainer.
This is especially relevant for young adults who had braces as teenagers in the Croydon, Ringwood or Bayswater area and are now in their twenties or thirties noticing their lower teeth crowding again. The pattern is predictable: the retainer was worn for a while, then forgotten, then lost, and the teeth quietly drifted.
Clear removable retainers wear out. They crack, they stain, and eventually they lose their shape. Expect to replace one every one to three years, depending on how well you look after it and whether you grind at night (grinding accelerates wear). Your dentist can take a new scan and have a replacement made.
Fixed retainers can last many years but may need rebonding if the adhesive fails. Some eventually need to be replaced entirely if the wire fatigues.
We fit retainers as part of every orthodontic treatment we complete. We use digital intraoral scans to fabricate removable retainers, which means no putty impressions and a precise fit. Fixed wires are bonded chair-side on the day the braces come off or at the appointment following aligner completion.
If you have had orthodontic treatment elsewhere and your retainer has been lost, broken, or no longer fits, we can assess the current position of your teeth and make a new one. If relapse has occurred, we can discuss realignment options.
We are at 59 Wicklow Ave, Croydon, a short walk from Croydon station on the Lilydale line. Patients from Heathmont, Bayswater, Mooroolbark and Kilsyth attend the practice regularly. Saturday appointments are available.
Call (03) 9725 8040 or book online. For more on the orthodontic options we offer, see our traditional braces and clear aligners pages.
This article is general information about orthodontic retainers. It is not personal dental advice. Your dentist will recommend the retainer type and wear schedule that suits your case.