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General product and regulatory information for laboratory, clinic and supply staff. It is not medical or dental advice and does not describe clinical technique.
Short answer
Dental impression material is a regulated medical device. Under 21 CFR 872.3660 it is a material such as alginate or polysulfide that is placed on a preformed impression tray to reproduce a patient’s teeth and gums, and FDA classifies it as Class II (Special Controls) under product code ELW.
Definition and scope
The FDA’s identification in 21 CFR 872.3660(a) reads: “Impression material is a device composed of materials such as alginate or polysulfide intended to be placed on a preformed impression tray and used to reproduce the structure of a patient’s teeth and gums.” The regulation states the purpose: to provide models for study and for production of restorative prosthetic devices, such as gold inlays and dentures. Paragraph (b) gives the classification: Class II (Special Controls). (Source: 21 CFR 872.3660, as published by the Cornell Legal Information Institute, checked 2026-10-30.)
The scope is the material that records the shape. The tray it is placed on, and any model made from it afterwards, are separate items.
How it is used in practice
The regulation describes the use at a high level only: the material goes on a preformed impression tray and reproduces the structure of teeth and gums, giving a record from which study models and restorative prosthetic devices are produced. Clinical technique belongs in the manufacturer’s instructions for use and in professional training, and this page does not cover it.
Types and standards
The CFR names two example materials, alginate and polysulfide, using the words “such as”, so the list is illustrative and not exhaustive. Standards address material families separately. ISO 4823:2025, “Dentistry – Elastomeric impression and bite registration materials”, was published on 2025-06-18 and states that it “specifies the requirements and their test methods for elastomeric impression and bite registration materials” (Standards Council of Canada standards database listing, checked 2026-10-30).
| Where you meet it | What the record says | Source |
|---|---|---|
| Federal regulation | 21 CFR 872.3660: impression material, Class II (Special Controls) | eCFR text via Cornell LII |
| FDA product classification | Product code ELW, device name “Material, Impression”, device class 2, dental review panel | openFDA device classification, dataset updated 2026-10-19 |
| Standards | ISO 4823:2025 covers elastomeric impression and bite registration materials | Standards Council of Canada listing |
Where it matters for labs, clinics and supply decisions
The openFDA record for product code ELW gives a practical lookup path for anyone documenting a supply item. It lists regulation number 872.3660, medical specialty Dental, and the flags below, as of the 2026-10-19 dataset:
- Device class 2, submission type 510(k).
- Not an implant and not life-sustaining or life-supporting.
- Third-party 510(k) review eligible (third_party_flag Y).
- GMP exempt flag N, so the device is not listed as exempt from good manufacturing practice requirements.
- Eligible for summary malfunction reporting.
Searching openFDA’s 510(k) endpoint on product code ELW returned 404 clearance records on 2026-10-30, the most recent being K254152 with a decision date of 2026-09-16. To read how the database is structured and searched, see FDA 510(k) data: what the database contains and how to search it. For the clearance pathway itself, see FDA 510(k) premarket notification and FDA clearance versus approval.
The same classification logic applies to neighbouring dental products; for example, dental composite resin is covered with its own FDA classification. For hearing-health work that also takes impressions of the ear, see earmold types, which covers a different device family.
Common misunderstandings
Is impression material just a consumable with no regulation?
No. Although it is used up in routine work, 21 CFR 872.3660 defines it as a device and classifies it Class II (Special Controls), and FDA lists it under product code ELW.
Is “alginate” the whole category?
No. The regulation names alginate and polysulfide as examples (“materials such as”), and ISO 4823:2025 separately addresses elastomeric impression and bite registration materials.
Is the impression the same as the final model or prosthesis?
No. The regulation describes the impression as the means to provide models for study and for production of restorative prosthetic devices; the models and prostheses are the downstream products.
FAQ
Is dental impression material regulated by FDA?
Yes. 21 CFR 872.3660 identifies it as a device and classifies it Class II (Special Controls); FDA’s classification database lists it as “Material, Impression” under product code ELW.
Which standard covers elastomeric impression materials?
ISO 4823:2025, “Dentistry – Elastomeric impression and bite registration materials”, published 2025-06-18.
Where can I look up cleared impression materials?
Search openFDA’s 510(k) records by product code ELW. See the section above and the guide to the FDA 510(k) database for how the records are structured.
Sources
- 21 CFR 872.3660, Impression material (Cornell Legal Information Institute), checked 2026-10-30.
- openFDA device classification, product code ELW, dataset last updated 2026-10-19, checked 2026-10-30.
- openFDA 510(k) records, product code ELW, checked 2026-10-30.
- ISO 4823:2025, Standards Council of Canada listing, checked 2026-10-30.
