Direct comparison
Night Guard vs Retainer: Purpose and FDA Status
Night guard vs retainer compared: what each is for, plus FDA status of the OTC mouthguard (code OBR) versus orthodontic appliances under 21 CFR 872.5410.
Written and maintained by CASRAI Editorial Board
Last updated
How do Night guard and Retainer compare side by side?
The table below compares Night guard and Retainer across 7 dimensions, from purpose in the sources to when each one applies.
Side-by-side comparison
| Dimension | Night guard | Retainer |
|---|---|---|
| Purpose in the sources | FDA's definition for the over-the-counter mouthguard code: to protect the teeth and reduce damage caused by bruxing or nighttime grinding, and to prevent the noise associated with bruxing and grinding. | The American Association of Orthodontists (AAO): a device designed to keep teeth in their straightened position after orthodontic treatment. |
| Situation it relates to | Bruxing (grinding) of the teeth, including at night. | The period after orthodontic treatment, when teeth tend to revert toward their original positions (AAO). |
| FDA device name and regulation | "mouthguard, over-the-counter", product code OBR, reviewed by the Dental panel. The record lists no regulation number. | Orthodontic appliances and accessories, 21 CFR 872.5410. The regulation names the expansion screw retainer; it does not name Hawley, clear or fixed retainers. |
| FDA device class | Unclassified (reason listed: Pre-Amendment). | Class I (general controls) for the 872.5410 device group. |
| Premarket route | Submission type 510(k). The FDA record shows GMP exempt: No. | Exempt from the 510(k) premarket notification procedures, subject to the limitations in 21 CFR 872.9. |
| Forms the sources describe | The FDA record covers over-the-counter mouthguards as one category. | AAO describes three types: Hawley (wire), clear, and fixed (permanent). Hawley and clear are removable; a fixed retainer is bonded in place. |
| When each one applies | When the question is protecting teeth from grinding. A dentist decides what a given person needs. | When the question is holding teeth in place after orthodontic treatment. AAO says the orthodontist decides which retainer a person wears. |
Sources
- FDA Product Classification database, code OBR "mouthguard, over-the-counter", read 2026-10-31: accessdata.fda.gov/scripts/cdrh/cfdocs/cfpcd/classification.cfm?id=OBR
- AAO, Retainers (aaoinfo.org/treatments/retainers/), read 2026-10-31
- 21 CFR 872.5410 (law.cornell.edu/cfr/text/21/872.5410), read 2026-10-31
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Common questions
Common questions about Night guard vs Retainer
Is a night guard the same as a retainer?
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No, the sources define them for different purposes. FDA's definition of the over-the-counter mouthguard (code OBR) is protection of the teeth from bruxing or nighttime grinding. AAO defines a retainer as a device that keeps teeth in their straightened position after orthodontic treatment.
Can a retainer be used as a night guard?
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The sources define the two devices for different purposes, and neither says one substitutes for the other. Whether a retainer is appropriate for a person who grinds their teeth is a question for their dentist or orthodontist.
Does FDA regulate night guards and retainers the same way?
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Not according to the records read. FDA lists the over-the-counter mouthguard (OBR) as Unclassified (Pre-Amendment) with a 510(k) submission type. Orthodontic appliances under 21 CFR 872.5410 are Class I and exempt from 510(k), subject to 21 CFR 872.9. That regulation names the expansion screw retainer, not every retainer type.
