Mandatory Retainer Wire: Everything You Need to Know

You have just finished your braces treatment, and you are being told about a retainer wire mandatory after your treatment. But what is its true purpose?

To get straight to the point, this thin metal or PEEK (medical polymer) wire is bonded behind the teeth to prevent them from shifting again. It is mandatory after treatment. In France, it must remain in place for 24 months, a reimbursed and regulated period, but it is recommended long-term to prevent relapse.

Is the retainer wire mandatory, and, more importantly, why?

Short answer: Yes, a fixed retainer is required for 24 months following dental treatment. After this period, it is no longer mandatory but remains highly recommended for life because teeth retain an ‘elastic memory’ and can shift again due to tongue pressure, chewing, or the natural aging of tissues.

Beyond the 24 reimbursed months – see our article dedicated to retainer wire costs for more information – (procedures TO75 and TO50), the stability of the teeth becomes the patient’s responsibility. However, biology does not stop there: tongue pressure, bone remodeling, and chewing habits continue to act.

the latest innovation in the dental industry, the PEEK retainer wire

Recent studies show that relapses can occur long after treatment completion. This is why many practitioners today recommend keeping — or replacing — the fixed wire for life.

To support this evolution, dental medicine has turned to solutions that are more comfortable in the long term. PEEK, the latest innovation, offers a discreet, hypoallergenic, comfortable, and MRI-compatible alternative, making prolonged wear much more acceptable.

Parents: Key Considerations for Mandatory Retainer Wire in Children

For younger patients, retention is far from a mere accessory: it secures an alignment that is still very fragile while facial growth continues.

The first two years are therefore fully covered (codes TO75 and then TO50 by health insurance), so that families incur virtually no additional cost. Without this wire, the lower incisors – already prone to crowding – will shift within the first few months after treatment completion; the drift then accelerates with the slightest omission of a retainer tray or the eruption of wisdom teeth. A significant risk, as resuming full treatment costs several thousand euros and adds further months of appliance wear.

In practice, the bonded wire is discreet, painless, and can be cleaned with an interdental brush; biannual check-ups allow the orthodontist to verify compliance and hygiene. It is therefore best to reassure the child: this small wire is simply the ‘seatbelt’ for their new smile.

Mandatory Retainer Wire in Children: Key Points to Know

• Covered Until Age 16
• Mandatory Retention for 24 Months
• Growth = High Risk of Shifting
• Premature Removal = Return to Treatment
• Discreet and Well-Tolerated Wire
• Biannual Check-ups Recommended

Adults: Freedom… But with Assumed Risk

After the age of sixteen, Social Security ceases all participation in orthodontic treatments; a broken retainer wire or one deemed unaesthetic therefore falls under personal budget, possibly aided by a mutual insurance company.

This autonomy and the resulting financial implications thus lead some to postpone replacement, especially if the breakage seems minor.

However, studies show that orthodontic relapse, i.e., tooth shifting, can still occur several decades after braces are removed.

Why Teeth Still Shift After Age 30

The end of growth does not mark the end of risks for dental alignment. The tongue exerts constant pressure on the teeth (lingual pressure), chewing consistently on one side (unilateral mastication) creates imbalances, and the natural aging of supporting tissues (gums, bone, ligaments) gradually reduces tooth stability.

It is precisely for these reasons that practitioners recommend keeping a retainer wire even in adulthood, even if it is no longer mandatory. It acts as an invisible barrier against these daily micro-shifts. Without this passive retention, teeth will shift — sometimes without the patient realizing it, often to the point of needing to consider new orthodontic treatment.

This phenomenon largely explains the rise of invisible aligners like Invisalign or Dr. Smile among adults: many patients who did not maintain their post-treatment retention in their youth are now seeking treatment to correct… what their teeth have undone.

Mandatory Retainer Wire in Adults: Key Takeaways

• Not Reimbursed After Age 16
• No Longer Mandatory After 24 Months
• Teeth Can Shift at Any Age
• Replacement Highly Recommended in Case of Breakage
• Relapse Often Invisible at First
• The PEEK Retainer Wire: The Most Comfortable and Durable Long-Term Solution

What Are the Alternatives to the Mandatory Metal Retainer Wire?

Among the alternatives to the mandatory metal retainer wire, night retainers are often mentioned. However, a retainer tray alone cannot legally replace a fixed wire within 24 months following orthodontic treatment. This period, known as ‘active retention,’ requires passive, continuous retention independent of patient compliance — a criterion that only a bonded solution can guarantee.

The PEEK Wire: The New Long-Term Standard

It is in this context that the PEEK retainer wire, offered by eZtain Lab, stands out as a true alternative to metal wire. Fully MRI-compatible, hypoallergenic, more flexible, and more comfortable, it offers the same clinical effectiveness as steel, while eliminating its drawbacks: imaging artifacts, oral discomfort, or allergy risk. Its discreet design makes it particularly suitable for long-term placement, including for adults who wish to avoid the metallic aesthetic.

As for the night retainer tray, it remains a complementary removable solution, sometimes added to the wire in cases of increased relapse risk (extractions, rotations, unstable occlusion). However, it can only be considered alone after the mandatory 24 months, and only if worn rigorously every night… for life.

Mandatory Retention – Comparison of Available Options

Solution	Advantages	Limitations & Legal Framework
Fixed Steel Wire	Full Independence, Clinical Track Record > 30 Years	Possible MRI Artifacts Requiring Removal, Risk of Breakage & Deformation
eZtain PEEK Fixed Wire	MRI-Compatible, Hypoallergenic, Very Comfortable	Approved as a Mandatory Retainer Wire by the Health Authority.
Night Retainer Tray	Removable, Covers Entire Arch, Zero Metal	Does Not Legally Replace the Wire for 24 Months; Effectiveness Depends on Constant Wear
Hawley Retainer	Adjustable, Can Correct Micro-Movements	Bulky, Visible; Same Legal Limitation as the Retainer Tray

Why a Retainer Tray Alone Is Still Not Recommended

While the night retainer tray may seem appealing at first glance – removable, discreet, comfortable – it is far from ideal as a sole retention solution. In reality, it is not recommended as an exclusive alternative, particularly for three major reasons:

• Legal Responsibility: The retainer tray relies on patient compliance (worn every night, for life), whereas the law requires passive and continuous retention during the 24 months post-treatment. In case of relapse, the orthodontist remains responsible for stability… which a removable appliance does not guarantee.
• Intermittent Effectiveness: As soon as it is forgotten (travel, fatigue, loss), teeth can begin to shift, sometimes within a few days. The effect is therefore not permanent and exposes to an invisible but real relapse.
• Wear, Loss, Cost: Made of thermoformed plastic, a retainer tray wears out, yellows, cracks… and must be regularly replaced. In the long term, the cumulative cost will exceed that of a fixed solution, for uncertain comfort.

Why Steel Retainer Wires Are Being Used Less and Less

Long used in orthodontics, the stainless steel retainer wire now shows its limitations for lifelong wear.

• Problematic MRIs: Metal creates artifacts that distort images, sometimes requiring the wire to be removed before a medical examination.
• Discomfort and Allergies: Its rigidity can cause daily discomfort, and its composition (notably nickel) can provoke reactions in some patients.
• Visible Aspect: Discreet in the short term, it becomes unaesthetic for permanent wear, especially in adults.

Today, as retention is designed to last a lifetime, steel wire appears increasingly less suitable. This is why materials like PEEK are gradually becoming the new standard.

Why Is a Retainer Wire Necessary?

Because it legally finalizes treatment for two years and medically blocks the elastic memory of the teeth. Without fixed retention, the risk of orthodontic relapse persists throughout life.

Legal Perspective: Guaranteeing the Result Under the Practitioner’s Responsibility

In France, the orthodontist has an obligation to guarantee a stable result after treatment. The Code of Ethics commits them to this, and case law (Cass. 2012) has already recognized faults in cases of absence or premature removal of retention. In short: without a retention device, treatment is considered incomplete.

This is why Social Security mandates two codified follow-up procedures (TO75 and then TO50), which systematically include a retainer wire. At this stage, a simple retainer tray is therefore not sufficient: it is removable, and thus dependent on the patient, whereas the law requires passive and continuous retention throughout the post-treatment period.

Parents: Obligations, Maintenance, and Long-Term Safety for Your Child

Will My Child Need to Wear the Retainer Wire for Life?

Yes, in the vast majority of cases, the retainer wire will be kept until the end of growth, and often well beyond.

A child does not finish orthodontic treatment with ‘frozen’ teeth: bone structures and supporting tissues (gums, periodontal ligament, etc.) continue to evolve throughout adolescence. Therefore, removing the retainer wire too early — often bonded behind the lower incisors, the area most prone to early crowding — exposes to rapid relapse.

This is why the current recommendation is clear: maintain fixed and passive retention for as long as it is well-tolerated by the child, including beyond the mandatory 24 months. This continuous retention requires no particular discipline from the young patient, unlike a removable retainer tray.

Early removal is only considered under two conditions:

• alignment stability is confirmed by the orthodontist at the end of growth;
• a rigorously worn night retainer tray is put in place to take over — and this for life

How to Help Your Child Maintain Their Retainer Wire?

A poorly maintained retainer wire can lead to detachment, inflammation, or even relapse. To avoid this, parents play a key role in the daily routine.

A toothbrush alone is not enough. You need to:

• use interdental brushes every evening;
• pass a rigid dental floss (super-floss) under the bonded wire;
• schedule a scaling every 6 to 12 months.

Parent Tip: Establish this routine as an evening habit, just like brushing. Some colorful or fun interdental brush models can make it easier for younger children to adopt.

Finally, remember to schedule a check-up every 3 months during the first year. This follow-up appointment (included in TO75/TO50 procedures for the first two years) also allows the orthodontist to check:

• bond integrity,
• wire tolerance in the mouth,
• and dental growth stability.

By establishing these practices early, you give your child the right habits to maintain their aligned smile long-term.

What to Do if the Wire Causes Discomfort or Detaches?

A wire that hurts the tongue is almost always partially detached or bent; in such cases, you should consult within 48 hours and protect your gums by adding dental wax to the ends of the wire.

During the consultation, the practitioner removes any residual adhesive, straightens or replaces the wire, and temporarily protects the mucous membrane with orthodontic wax if necessary.

Adults: Managing Breakage, Imaging, and Aesthetic Preferences

Broken Wire: Replace It Quickly to Avoid Relapse… and Costs

After the two-year post-treatment period, the retention wire is no longer legally mandatory for adults. However, a broken retention wire remains a major risk: as soon as a segment detaches, teeth begin to shift, sometimes within a few days.

Seemingly benign, untreated breakage can lead to:

• orthodontic relapse visible within a few months,
• a return to full treatment (aligners or braces) costing several thousand euros,
• a lasting loss of the achieved result after years of effort.

However, re-bonding a wire costs a maximum of a few hundred euros in most cases, for a 15-minute session.

Do you want to prevent this from happening again?

Switch to a PEEK wire. Thanks to its flexible polymer structure, derived from medical technologies (surgery, implantology), it has shown no cases of breakage in 10 years of clinical use. Custom-made to perfectly fit your dental arch, it withstands daily stresses while remaining invisible, comfortable, and MRI-compatible.

It’s the ideal choice for an aligned smile that stays that way.

Stress-Free MRI: Undergo Imaging Without Compromising Retention

In the case of a brain or ENT MRI, a metal retention wire can disrupt medical images (artifacts), making the examination difficult to interpret. Until now, the classic solution involved temporarily removing the wire, then re-bonding it immediately afterward — an unreimbursed, time-consuming, and stressful procedure, to be repeated with each new examination.

To avoid these constraints, more and more practitioners today recommend the definitive switch to a PEEK wire, which is fully MRI-compatible. This innovative material produces no image distortion, while ensuring continuous alignment stabilization.
This offers significant comfort, especially if you require multiple examinations over the years.

Wire-Free Smile: Conditions and Safe Alternatives

To remove the wire for aesthetic reasons or comfort, the orthodontist verifies that the occlusion remains stable; in return, a lifelong night guard must be worn flawlessly. Without discipline, the risk of tooth migration increases rapidly, and with it, the risk of needing aligner treatment again in the future.

Conclusion – The Mandatory Retention Wire: The Most Important Step After Your Treatment.

The answer is clear: yes, fixed retention is mandatory for the first two years and remains the best way to maintain your new alignment throughout life. Removable alternatives, MRI, late breakage: in every scenario, maintaining reliable retention remains the most economical and safest decision. eZtain’s PEEK wires combine comfort, aesthetics, and MRI compatibility, while offering the same strength as a steel wire; they thus simplify long-term wear, whether protecting the smile of a growing child or securing the result for adults. For a check-up, re-bonding, or switching to PEEK, a simple appointment is all it takes.

Your smile deserves it.

About the Author

Dr. Nicolas Philippides is an orthodontist, graduated from the University of Strasbourg, and holds a postgraduate degree (CES) in dentofacial orthopedics. With several years of clinical practice, he has treated hundreds of patients, maintaining a constant focus on long-term stability and comfort.

Confronted with the limitations of conventional retainers, he founded eZtain Lab in 2022—a project born from a simple yet recurring clinical observation: too many relapses caused by poorly adapted or fragile retainer wires. In collaboration with INSA, he developed a new generation of custom-made PEEK retainer wires, designed to be comfortable, durable, and precisely adapted to each patient.

Today, his research and clinical experience are driven by a single ambition: to offer reliable devices, built to last, and fully aligned with the demands of modern orthodontics.