Memotain vs eZtain: Which retainer to choose for your patients?

In addition to classic bent steel wire, orthodontists now have two main custom fixed retention solutions: Memotain, a Nitinol wire machined via CAD/CAM, and eZtain, a PEEK (biocompatible polymer) wire machined to the micron. On paper, both technologies aim to reduce debonding, offer better comfort, and ensure post-treatment stability, but what is the reality?

In practice, Memotain relies on a solid clinical history and a shape-memory alloy that ensures precise adaptation, but it finds its limits in the material’s strength and its fracture rate.

In parallel, eZtain offers an innovative alternative: a metal-free, aesthetic, hypoallergenic material, invisible on radiological examinations, and designed to limit emergencies. Its digital workflow is simplified: STL file submission, machining, bonding that no longer requires a transfer, and its fracture rate is 0% to date.

For practitioners, the choice therefore depends on the patient profile and the time they wish to save in the practice.

What are the differences between Memotain and eZtain?

Unlike Winnove, which only impacts the retainer’s format, Memotain and eZtain differ in terms of material.
While eZtain uses PEEK, a metal-free material, Memotain relies on Nitinol, a shape-memory alloy.

Both solutions adopt a radically different approach compared to retention wire:

• Memotain relies on Nitinol, a nickel-titanium alloy known for its shape memory. Its CAD/CAM design and electrolytic polishing offer high adaptation precision and a very smooth surface. This material, well-documented in orthodontic literature, has proven its worth in terms of comfort and patient experience.
  
• eZtain, conversely, focuses on PEEK (polyetheretherketone): a medical polymer already used in surgery and implantology and known for its biocompatibility. Completely metal-free, it prevents allergic reactions and eliminates the metallic taste sometimes reported with alloys. Another key advantage: PEEK is invisible in imaging (MRI, X-rays), which is an asset in managing patients requiring frequent medical follow-ups.
  

Furthermore, both solutions implement digital machining for their product. However, Memotain is machined on a single plane, while eZtain is machined in all three spatial planes, offering perfect adaptation to the tooth surface.

Memotain or eZtain: Which is more comfortable for your patient?

In terms of comfort, eZtain avoids metallic taste and rigidity in the gingival environment, and its micron-level machining minimizes patient friction. Memotain, on the other hand, focuses on the thinness and precision of the Nitinol wire.

As always in orthodontics, patient comfort is often crucial for long-term retainer acceptance.
Both solutions implement major technological innovations to best address this.

• Memotain, thanks to its ultra-fine wire and CAD/CAM design, adapts precisely to the lingual surface. Its minimal bulk limits occlusal interferences and discomfort in phonation. However, some patients report a metallic taste or a sensation of rigidity, and more frequent breakage represents a major inconvenience.
  
• eZtain changes the game thanks to its PEEK wire. Metal-free, it eliminates any taste perception and offers gentle flexibility, closer to a natural feel. The polished surface limits tongue irritation and provides lasting comfort, especially for adult patients who are demanding about aesthetics and intra-oral sensation.
  

In practice, Memotain is known for its thinness, but eZtain stands out for its more neutral sensory comfort and better long-term acceptability.

Which solution is the most hygienic?

Hygiene is a central issue in fixed retention, as any relief or roughness can quickly become a plaque accumulation point.

Memotain benefits from electrolytic polishing, which makes the Nitinol wire very smooth and thus less conducive to bacterial adhesion than classic manually bent and bonded wires.

For its part, eZtain relies on the digital machining of PEEK and precision polishing, which give the surface perfect uniformity, making it non-porous and metal-free. This characteristic further limits deposits and facilitates daily cleaning.

For patients with a tendency towards gingival inflammation or increased plaque sensitivity, this advantage is particularly significant. While both technologies clearly improve the situation compared to traditional steel wires, eZtain’s polymer material seems to offer an even more favorable environment for periodontal health.

What is the impact on the orthodontist’s daily practice?

The impact of a retention system goes far beyond just the stability of results. It also dictates chair time, workflow fluidity, and emergency management. Comparing Memotain and eZtain from this perspective allows for an evaluation of their direct influence on the efficiency and daily organization of an orthodontic practice.

Digital Workflow and Placement Protocol

• Memotain: manufactured via CAD/CAM, it requires indirect bonding with a transfer jig, which extends appointment time and increases the risk of error. The average lead time is approximately 10 business days. There is no direct connection with intra-oral scanners, which disrupts clinical organization during ordering.
  
• eZtain: the practitioner sends an STL file directly from their intra-oral camera; the PEEK wire is then machined and placed via indirect bonding, without necessarily requiring the use of a transfer. The workflow is simpler, and lead times are generally shorter.
  eZtain Lab is compatible with all intra-oral scanners on the market, thus eliminating any friction for the orthodontist.

Chair Time

• With Memotain, indirect bonding via jig may require longer operative time and greater involvement from the orthodontist’s assistant.
  
• With eZtain, indirect placement without a transfer shortens the procedure time, and its simplicity reduces the learning curve for the clinical team.

The latest internal studies by eZtain Lab estimate the placement time for an eZtain retainer at 4 minutes, compared to the usual 6 to 8 minutes. However, eZtain truly stands out in calendar management. By avoiding emergency appointments for breakage or debonding, eZtain simplifies practice management and increases billable time.

Emergencies and Unforeseen Interventions

• Memotain: due to its thinness, the Nitinol wire remains brittle. Various independent studies highlight this point. Each of these incidents involves an emergency visit, a repair, or even a complete remanufacture.
  
• eZtain: thanks to PEEK and its digital machining, clinical feedback is remarkably stable. After more than 5 years of use (as of 2025), the fracture rate remains 0%.

Indirect Economic Impact

An orthodontic practice must optimize its appointments. Each unscheduled emergency has a hidden cost:

• loss of clinical time,
  
• scheduling disruption,
  
• decrease in patient satisfaction.
  

eZtain, by concretely reducing the number of repairs, can improve overall ROI: the practitioner spends less time on maintenance and more on scheduled, billable procedures.

Learning Curve and Team Adaptation

The ease with which a clinical team adopts a placement protocol directly influences the speed of implementation and the reduction of daily errors.

• Memotain: placement with a jig requires specific training and particular rigor. Young assistants or practitioners in training must familiarize themselves with the method.
  
• eZtain: the keyless bonding protocol, which is more intuitive, is generally quicker for the team to master thanks to the retainer’s perfect adaptation to the tooth surface.

Memotain or eZtain: Which is the most cost-effective solution for the practice?

The difference between the two solutions does not truly lie in their purchase cost, which remains similar, but in their overall profitability. This is primarily determined by maintenance costs and the disruption caused in the practice by unforeseen emergencies.

Initial Acquisition Cost

• Memotain: the wire’s price is competitive, comparable to other high-end retainers. The manufacturer’s warranty (often 24 months) secures the initial investment.
  
• eZtain: the unit cost is of the same order of magnitude. The material’s innovation (PEEK) does not represent a prohibitive additional cost and remains accessible for a standard orthodontic practice.
  

Hidden Costs and Maintenance

• Memotain: in case of fracture or debonding, one must anticipate:
  
  • unforeseen operative time (emergency),
    
  • sometimes complete remanufacture of the wire,
    
  • additional logistical and administrative costs.
    Even if cases are rare, each incident represents an expenditure of time and resources.
    
• eZtain: thanks to its mechanical resistance and flexibility, the reported fracture rate is almost zero in some clinical testimonials. Fewer emergencies = fewer unforeseen costs. This directly translates to better control of operational expenses.
  

Clinical Time ROI for Your Practice

Time is the most expensive resource in orthodontics. Let’s see how Memotain and eZtain compare in managing it.

• Memotain: managing emergencies or remanufactures often takes the place of a scheduled, billable appointment.
  
• eZtain: by limiting these unforeseen events, the practitioner retains their slots for valuable procedures (consultations, new patients). Over a year, this represents a significant productivity gain.
  

Patient Satisfaction and Retention

A patient recalled multiple times for a breakage generates:

• a perceived negative experience,
  
• a risk of unfavorable word-of-mouth,
  
• an emotional burden for the practice (emergency stress).
  

With a more stable device:

• eZtain enhances long-term satisfaction,
  
• and better retention indirectly contributes to profitability (less management of dissatisfied patients, better local reputation).
  

eZtain vs Memotain Comparison Table

Conclusion

Memotain and eZtain embody two modern approaches to custom orthodontic retention.

Memotain capitalizes on the Nitinol alloy, known for its thinness and precise adaptation, with a solid clinical history and several supporting scientific publications.

eZtain, for its part, introduces a true material breakthrough with PEEK: a biocompatible, metal-free polymer, invisible in imaging, simpler to place, and designed to minimize emergencies.

Ultimately, the choice will depend on the patient profile and the practice’s strategy. Practitioners committed to scientific continuity and the use of shape-memory alloys will find a proven solution in Memotain.

But for those who wish to limit unforeseen events, optimize their operative time, and meet a growing demand for aesthetics and safety, eZtain appears as a particularly credible, innovative, and future-oriented alternative.

Feel free to read more of our comparisons betweeneZtain and Winnove as well as our comparisons between Invisalign and Dr. Smile

Are you a practitioner and want to know more? Book an appointment now.