Written and maintained by CASRAI Editorial Board
Last updated
General product information only, not dental or medical advice. Clinical decisions belong to a licensed dentist.
Short answer
Cavity varnish is a dental device that FDA defines as a compound intended to coat a prepared cavity of a tooth before restorative material is placed. It is regulated under 21 CFR 872.3260 as Class II (special controls). It is not the same product as the topical fluoride varnish painted on tooth surfaces, even when a cavity varnish contains sodium fluoride.
Definition and scope
21 CFR 872.3260 (eCFR, checked 2026-10-31) says: “Cavity varnish is a device that consists of a compound intended to coat a prepared cavity of a tooth” before insertion of restorative materials. The same section says the device is intended to prevent penetration of restorative materials, such as amalgam, into the dentinal tissue, and classifies it as Class II (special controls). FDA’s product code for the device type is LBH.
The section also carves out one narrow exemption: the device “when it is an external cleaning solution” is exempt from premarket notification, subject to the limitations in 21 CFR 872.9. That does not mean every cavity varnish is exempt. For how classes and premarket routes differ, see FDA medical device classification and the 510(k) premarket notification guide.
How it is used in practice
The manufacturer’s instructions for use (IFU) state what a specific product is for. Prevest DenPro’s COPAL-F “Cavity varnish with fluoride” (IFU rev 07, 23-05-2023) describes a copal gum based protective varnish for insulating exposed dentine that reduces penetration of fluids into the tooth and the restoration placed afterwards. Its stated intended use is “cavity liner and dentinal tubuli sealer”, and its indications include lining cavities and use as an immediate varnish prior to insertion of amalgam, cement or composite fillings. The IFU adds that the sodium fluoride “provides a thermal barrier for deep restoration”.
Related materials
Cavity varnish with and without fluoride
The COPAL-F composition is copal gum, isopropyl alcohol and sodium fluoride. Fluoride is therefore an ingredient of that product, not part of FDA’s definition of the device type.
Varnish and separate solvent
One supplier listing for Temrex Copalite (Dental City, checked 2026-10-31) describes a cavity liner applied under gold and amalgam restorations, made of a varnish plus a separate solvent that acts as a thinning agent, sold as a kit, varnish only or solvent only. This is a supplier description, not a regulator or manufacturer IFU statement.
Not the same as topical fluoride varnish
FDA’s definition covers a coating for a prepared cavity. Topical fluoride varnish is a different product category; see fluoride varnish vs fluoride gel. For another dental coating category with its own FDA class, see pit and fissure sealant.
Where it matters for labs, clinics and supply decisions
A label-reading checklist drawn from the COPAL-F IFU shows what supply and clinic staff can confirm before a product is stocked or used:
| IFU item | What COPAL-F’s IFU states |
|---|---|
| Composition | Copal gum, isopropyl alcohol, sodium fluoride |
| Intended use | Cavity liner and dentinal tubuli sealer |
| Contraindication | Allergy to any component |
| Hazard and label symbols | Harmful irritant, flammable, non-sterile, keep dry, professional dental use only |
| Warnings | Avoid prolonged skin or eye contact (allergic contact dermatitis) and prolonged inhalation; not for internal use |
| Storage | 10-24 C (50-75 F), cap closed, away from moisture |
| Shelf life | 3 years from manufacture |
| Presentation | 1 x 15 ml glass bottle with dropper (Ref 40027) |
| Disposal | According to local rules |
Other products will differ, so read each product’s own IFU. A safety data sheet is a separate document; see how to read a safety data sheet.
Common misunderstandings
- “With fluoride” does not make it a topical fluoride varnish. FDA defines cavity varnish by where it is used, a prepared cavity.
- Class II is not “exempt”. The 872.3260 exemption applies only to the device when it is an external cleaning solution.
- It is not sterile. The COPAL-F label carries a non-sterile symbol.
- It is for professional use. The same label states professional dental use only.
FAQ
What is cavity varnish?
Under 21 CFR 872.3260, a device consisting of a compound intended to coat a prepared tooth cavity before restorative materials are inserted. FDA classifies it as Class II (special controls).
Is cavity varnish the same as fluoride varnish?
No. FDA defines cavity varnish by its use on a prepared cavity. Some cavity varnishes, such as COPAL-F, contain sodium fluoride, but that does not change the device type.
Is cavity varnish exempt from premarket notification?
Not in general. 21 CFR 872.3260 exempts only the device when it is an external cleaning solution, subject to the limitations in 21 CFR 872.9.
Is cavity varnish sold sterile?
The COPAL-F label carries a non-sterile symbol. Other products differ, so check each product’s IFU.
Sources
- 21 CFR 872.3260, Cavity varnish, eCFR, https://www.ecfr.gov/current/title-21/section-872.3260 (checked 2026-10-31).
- Prevest DenPro, COPAL-F Cavity varnish with fluoride, IFU rev 07, 23-05-2023, https://www.prevestdenpro.com/wp-content/uploads/2021/08/Copal-F-IFU.pdf (checked 2026-10-31).
- Dental City, Temrex Copalite supplier listing, https://dentalcity.com/product/11822/temrex-copalite (checked 2026-10-31).
