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General product and regulatory information for lab, clinic and supply staff. It is not clinical advice and does not describe any procedure.
Short answer
An orthodontic power chain is a connected strip of elastomeric (stretchable) rings used in fixed orthodontic treatment to apply force between teeth, most often for space closure. The force fades once it is stretched, mostly within the first day. In the United States, power chains are not named in FDA’s orthodontic appliance regulation; the nearest listed device, the orthodontic elastic band, is Class I.
Definition and scope
An elastomeric chain, also called a power chain or elastic chain, is a run of linked rings made from stretchable polymer. A 2024 laboratory study in Cureus describes elastomeric chains as widely used for incisor retraction and space closure, and notes that the force they exert diminishes over time (Cureus 2024, PMC11495140, checked 2026-10-31).
The same study lists other ways to deliver space-closing force, including coil springs, retraction springs, loop mechanics and magnets, so a chain is one force-delivery option among several. Related small orthodontic consumables are covered in our guide to orthodontic separators and how FDA classifies them.
How it is used in practice
In the study’s bench set-up, each chain sample had four loops and was stretched to 25 mm, then held in artificial saliva at 37 °C. The test group also received simulated tooth movement (0.25 mm per week of jig closure) and a fluoride rinse regimen; force was measured at engagement, 1 hour, 4 hours, and at 1, 7, 14, 21 and 28 days. Eighty samples from four brands were tested: AlastiK (3M), Generation II Power Chain (Ormco), Elastic Chain (Morelli) and Plastic Chain (American Orthodontics).
This page does not describe how chains are placed or changed in a patient; that is clinical work for a licensed orthodontist.
Is an orthodontic power chain an FDA-regulated device?
Orthodontic appliances are medical devices under 21 CFR 872.5410, “Orthodontic appliance and accessories” (Cornell LII copy of the eCFR, checked 2026-10-31). The regulation defines the device as one intended for use in orthodontic treatment that is affixed to a tooth so that pressure can be exerted on the teeth. Its list of included devices names the orthodontic elastic band, band, bracket, wire clamp, space maintainer, expansion screw retainer, spring, tube and wire. It does not name power chains, so a power chain should not be assumed to fall under that entry.
The regulation classifies the listed devices as Class I (general controls) and exempts them from premarket notification (510(k)), subject to the limitations in 21 CFR 872.9. The openFDA classification database lists product code ECI, “Band, Elastic, Orthodontic”, under the Dental panel as device class 1 with regulation number 872.5410 (checked 2026-10-31). ECI is the closest elastic-band code, not a confirmed code for power chains. For background on how device classes arose, see Medical Device Amendments of 1976.
Types and related concepts
Consumer-facing sources describe power chains by the spacing between rings: continuous (closed), short and long. Exact spacing values vary between sources and manufacturers, so check the manufacturer’s own specification rather than relying on a general label (spacing terminology from Healthline, a consumer health site).
How much force does an elastomeric chain lose over time?
Most of the loss comes early. In the Cureus study, maximum force degradation occurred at one day for all four chain materials in both groups, followed by steady loss over 28 days. Under plain artificial saliva (control), no significant difference between materials was found. With simulated tooth movement and fluoride rinse (test), significant differences appeared.
| Chain (test group, simulated oral conditions) | Force decay at 28 days |
|---|---|
| Plastic Chain, American Orthodontics (highest decay) | 67.9 ± 6.24% |
| Generation II Power Chain, Ormco (lowest decay) | 51.9 ± 9.78% |
These are in-vitro results; bench conditions differ from a patient’s mouth.
Where it matters for labs, clinics and supply decisions
Questions worth asking when reading a chain product listing or specification:
- Material and brand: the study found material-dependent decay differences under simulated oral conditions, so the brand and polymer matter to any force claim.
- Test conditions behind a force figure: stretch length, temperature, medium (dry, water or artificial saliva) and time point. In the study the largest drop was in the first day, so a figure measured at engagement says little about force after a week.
- Spacing style: continuous, short or long, as defined by the manufacturer.
- Regulatory status: whether the manufacturer states a classification, and that 21 CFR 872.5410 does not list power chains by name. See what FDA establishment registration does and does not mean.
Dental and oral-health research context is outlined in What Is Dental and Oral Health Research?.
Common misunderstandings
- “Force stays constant until the chain is changed.” In the study, force fell most in the first 24 hours and kept falling over 28 days.
- “A Class I device is unregulated.” Class I devices remain under general controls; being exempt from 510(k) is not the same as being exempt from FDA oversight. Adverse events involving devices fall under Medical Device Reporting.
- “All brands behave alike.” Only under the control conditions did the study find no significant difference between materials.
FAQ
What is an orthodontic power chain?
A connected strip of elastomeric rings used in fixed orthodontic treatment to apply force between teeth, commonly for space closure.
Is an orthodontic power chain an FDA-regulated device?
Orthodontic appliances and accessories are regulated under 21 CFR 872.5410 as Class I devices exempt from 510(k) subject to 21 CFR 872.9, but the regulation’s list does not name power chains. The nearest listed device is the orthodontic elastic band.
How much force does an elastomeric chain lose over time?
In one 2024 laboratory study, decay at 28 days under simulated oral conditions ranged from 51.9% to 67.9% depending on brand, with the largest loss in the first day.
Sources
- 21 CFR 872.5410, Orthodontic appliance and accessories: law.cornell.edu/cfr/text/21/872.5410 (checked 2026-10-31).
- openFDA device classification, product code ECI: api.fda.gov (checked 2026-10-31).
- Force Decay Behavior of Orthodontic Elastomeric Chains in Simulated Oral Conditions, Cureus 2024: PMC11495140 (checked 2026-10-31).
- Healthline, power chain braces (terminology only): healthline.com (checked 2026-10-31).
