Just because your braces are off doesn't mean your teeth are ready to stay put.

Your teeth may have moved to their new positions, but the supporting structures—like the periodontal ligament, jawbone, muscle balance, and your bite—still need time to remodel and adapt.

That's why retention is not an optional extra. It's the essential final stage of orthodontic treatment. Without it, all that hard work could slowly reverse itself—and your teeth might just wander back to where they started. 

The early form of the lingual fixed retainer can be traced back to the 1970s. Knierim first proposed bonding stainless steel wire to the lingual surfaces of the mandibular anterior teeth to maintain post-orthodontic stability. Early fixed retainers commonly used relatively large-diameter stainless steel round wire, usually bonded only to the lingual surfaces of the mandibular canines, with the primary purpose of maintaining intercanine width. Later, as clinicians gained a deeper understanding of mandibular incisor relapse, retainer design gradually evolved from two-end canine bonding to continuous bonding across the six mandibular anterior teeth. Salehi et al. summarized this development in their study background: the first generation of fixed retainers used large-diameter stainless steel round wires of 0.030-0.032 inch, followed by smaller-diameter braided or coaxial round wires that could be bonded to all mandibular anterior teeth.

Demostration of twisted retainer wires using

The introduction of multistranded twisted wire was an important milestone in the development of lingual fixed retention. Around 1983, Zachrisson introduced the multistranded twisted retainer, which was bonded in a spiral form to the lingual surfaces of the six mandibular anterior teeth. The multistranded structure helps reduce stress concentration in the bonding material, thereby reducing the risk of debonding. A 0.0195-inch multistranded stainless steel twisted wire has been reported to perform well in some studies; it is relatively thin while offering a practical balance of rigidity and flexibility, allowing a certain degree of physiological tooth mobility.

Clinical use of fixed retainer wires

The core purpose of metal twisted and braided lingual retainer wires is to help maintain anterior alignment, arch width, and post-treatment dental stability after fixed-appliance or clear-aligner therapy. They are bonded to the lingual surfaces of the teeth with resin. Common clinical applications include:

● Mandibular anterior 3-3 fixed retention.

This is the most classic indication, especially after correction of mandibular anterior crowding, derotation of anterior teeth, space closure in extraction cases, or in cases requiring long-term maintenance of lower anterior alignment.

● Maxillary anterior fixed retention.

In selected cases, fixed retainer wire may also be used on the lingual surfaces of the maxillary anterior teeth. However, maxillary applications require additional consideration of occlusal contact, available bonding space, and wire thickness.

● Combined use with removable or vacuum-formed retainers.

In recent years, many retention protocols have used a combination of a vacuum-formed retainer and a fixed lingual retainer wire to support both overall arch maintenance and precise anterior stability.

The advantages of stainless steel and other metal materials in orthodontic retention first come from their mature material properties. Metal retainer wires offer favorable strength, toughness, and dimensional stability, allowing them to provide reliable support under complex oral functional forces. Reviews on orthodontic retainers have suggested that the relatively favorable performance of metal wires may be related to their higher material stiffness; stainless steel, in particular, can provide good toughness under multidirectional functional loading.

Compared with fiber-reinforced composites, metal wires have a distinct practical clinical advantage: their performance is more predictable, and clinicians are more familiar with the procedures of bending, bonding and repairing them. Admittedly, metal retainer wires are not suitable for all patients. For certain individuals, particularly those with nickel allergies, dentists need to adopt nickel-free alternatives. Nevertheless, multi-strand stainless steel retainer wires remain a proven, cost-effective and reliable option for most routine clinical cases.

Three-point force measuring instrument for measuring the toughness of metal wires

Metal twisted wires, coaxial wires, and braided wires are not made from a single solid wire. Instead, they are formed from multiple fine strands through twisting, coaxial arrangement, or braiding. This structure allows the wire to combine flexibility, resilience, and a certain degree of rigidity even at smaller diameters.

From a mechanical perspective, multistranded structures provide several key advantages:

✅Easier passive adaptation to the lingual tooth surface. In clinical studies, 0.0175-inch multistranded stainless steel retainer wires were carefully adapted on a working model before being bonded to the lingual surfaces of the anterior teeth. Passive adaptation is critical because any active stress during bonding may cause unwanted tooth movement.

✅Stability with a degree of physiological tooth mobility. A fixed splint that is too rigid may restrict normal tooth micro-movement and increase stress at the bonding interface. One of the clinical values of multistranded twisted wire lies in its balance of rigidity and flexibility: it can help limit visible relapse without completely locking physiological tooth movement. Thinner multistranded wires can combine rigidity and flexibility while allowing limited physiological mobility.

✅Better stress distribution through a multistranded structure. Spiral or braided structures can help distribute functional forces and bonding-interface stress, reducing local stress concentration. The multistranded form has been reported to reduce stress concentration in the bonding material and may therefore lower the risk of debonding.

✅Favorable elasticity and force behavior. Taneja et al. tested 20 designs of multistranded stainless steel orthodontic wires using a three-point bending test, including 3-strand twisted wires, 5- and 6-strand coaxial wires, and 8- and 9-strand braided rectangular wires. The study showed that although unloading force levels varied by structure, cross-section, and number of strands, multistranded stainless steel wires generally demonstrated favorable elastic behavior with low mean permanent deformation. The study also indicated that multistranded stainless steel wires can deliver relatively light and effective force levels within certain ranges.

Schematic diagram of the cross-section of three different types of multi-strand retainer wires

Removable retainers, such as Hawley retainers and vacuum-formed retainers, are easy to fabricate. However, their effectiveness relies on patients wearing them as required. Poor compliance or insufficient wearing time may compromise long-term retention outcomes. Most patients also complain that removable retainers cause significant foreign body sensation, impair appearance and affect pronunciation, which further discourages prolonged wear.

In contrast, fixed lingual retainers are bonded to the lingual surfaces of teeth by clinicians. They require no daily removal and reinsertion by patients and can deliver continuous retention. Additionally, they are inconspicuous, do not affect the esthetics of anterior teeth, and have minimal impact on pronunciation and daily social interactions, so they enjoy high patient acceptance.

This is one of the key reasons why metal twisted lingual retainer wires remain popular among clinics: their value is not only material-based, but also clinical-management-based, because they help reduce relapse risk caused by insufficient patient compliance.

Glass fiber and polyethylene fiber materials have also been introduced for fixed lingual retention. Their advantages include esthetics, a metal-free appearance, and suitability for some patients with metal sensitivity. However, fiber-based retainers may form a relatively rigid splint that limits physiological tooth movement. Their clinical performance can also be affected by the fiber material, surface treatment, resin penetration, and bonding technique.

At present, the overall quality of evidence on fixed-retainer failure rates remains limited, and no absolute conclusion can be drawn across all materials and protocols. However, multistranded metal retainers are among the most extensively studied categories. For clinics and distributors, the value of metal twisted and braided retainer wires is not only their cost-effectiveness and durability, but also their long history of clinical use, strong clinician familiarity, and well-established operating procedures.

3 main kinds of retainers

    For clinics, a high-quality metal twisted or braided lingual retainer wire should meet three key requirements: stable material performance, good bendability, and reliable bonding adaptation. It must be flexible enough to passively adapt to lingual tooth anatomy on the model or in the mouth, while also remaining stable enough to withstand daily chewing forces, tongue pressure, and the micro-movements of the dentition.

    For distributors, metal multistranded retainer wire is a foundational orthodontic consumable with stable repeat demand. It covers the retention stage after both fixed-appliance and clear-aligner therapy, is suitable for adolescent and adult orthodontic cases, and can also be combined with vacuum-formed retainers as part of a dual-retention protocol. With clear clinical value, broad applicability, and strong clinician familiarity, it is a product category worth maintaining as part of a long-term orthodontic portfolio.

Use of braided retainer wires

The researches and development of metal twisted/braided lingual retainer wires reflect the shift in orthodontic retention philosophy from "simply maintaining canine width" to "long-term stabilization of anterior tooth alignment". Featuring a multi-strand braided compressed flat structure and processed with heat treatment, these wires deliver excellent flexibility, stress distribution and passive adaptation. They thus possess high clinical value for permanently retaining teeth in correct positions. For dental clinics and distributors prioritizing reliability, operational familiarity and stable supply, high-quality multi-strand metal lingual retainer wires remain a classic option for orthodontic retention protocols.

Ai, Y., Zou, C., Wu, S., Tu, S., Wang, Z., Yu, X., & Tang, K. (2016). Effects of two types of lingual fixed retainers on periodontal health. Journal of Foshan University (Natural Sciences Edition), 34(3), 70-73.

Green, J. I. J. (2015). Dental materials: The multi-stranded wire retainer. BDJ Team, 1, Article 15054.Iliadi, A., Kloukos, D., Gkantidis, N., Katsaros, C., & Pandis, N. (2015). Failure of fixed orthodontic retainers: A systematic review. Journal of Dentistry, 43(8), 876-896.

Knierim, R. W. (1973). Invisible mandibular cuspid to cuspid retainer. The Angle Orthodontist, 43, 218-219.

Salehi, P., Zarif Najafi, H., & Roeinpeikar, S. M. (2013). Comparison of survival time between two types of orthodontic fixed retainer: A prospective randomized clinical trial. Progress in Orthodontics, 14, Article 25.

Taneja, P., Duncanson, M. G., Jr., Khajotia, S. S., & Nanda, R. S. (2003). Deactivation force-deflection behavior of multistranded stainless steel wires. American Journal of Orthodontics and Dentofacial Orthopedics, 124(1), 61-68.

Yang, Y. (2015). The clinical effectiveness of flexible spiral wire lingual fixed retainer in orthodontics [Master's thesis, Xinjiang Medical University].

Zachrisson, B. U. (1977). Clinical experience with direct-bonded orthodontic retainers. American Journal of Orthodontics, 71(4), 440-448.

Niu, Y., Yuan, R., Li, M., Qi, K., Lu, Z., & Si, H. (2026). Clinical comparative study of vacuum-formed retainers combined with CAD/CAM pure titanium lingual wires and traditional stainless steel twisted lingual wires after orthodontic treatment. Clinical Journal of Medical Officers, 54(4), 354-358.