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General product information only, not medical or clinical advice. Technique and instrument selection belong to the treating clinician and the manufacturer’s instructions for use.
Short answer
A diamond bur is a rotary dental instrument: a shaft that fits a handpiece and a head with diamond chips embedded in it, which abrades a surface as it rotates. In the United States, the FDA lists it as a Class I device, exempt from 510(k) premarket notification, under 21 CFR 872.4535. Grit color rings are set by each manufacturer, so a color means nothing until it is read against that maker’s own chart.
Definition and scope
The regulation calls it a “dental diamond instrument” and defines it as “an abrasive device intended to smooth tooth surfaces during the fitting of crowns or bridges.” It “consists of a shaft which is inserted into a handpiece and a head which has diamond chips imbedded into it. Rotation of the diamond instrument provides an abrasive action when it contacts a tooth.” (21 CFR 872.4535(a), checked 2026-10-31.)
Under the same section the device is “Class I” and “exempt from the premarket notification procedures in subpart E of part 807.” The text dates from 52 FR 30097 (12 August 1987), as amended in 1994.
How it is used in practice
The regulatory description is mechanical: the shaft seats in a handpiece, and rotation turns the diamond-coated head into an abrasive. The handpiece is a separate device with its own care requirements; see our guide to handpiece lubricant for what drives a bur or tip. This page does not cover clinical technique.
Grit and color coding: one maker’s chart
Manufacturers mark the grit of a diamond bur with a colored ring on the shaft. Komet USA publishes its own chart (A Guide to Dental Instrument Color Codes: Diamonds, May 2022). It describes coarser burs as used for cutting, medium grit burs for operative dentistry, and finer burs for finishing.
| Komet ring color | Grit | Particle size (microns) | Komet’s stated use |
|---|---|---|---|
| Purple | Extra-coarse | 230 | Cutting |
| Black | Super-coarse | 180 | Cutting |
| Green | Coarse | 151 | Cutting |
| No color | Medium | 107 | Operative dentistry |
| Red | Fine | 46 | Finishing |
| Yellow | Extra-fine | 25 | Finishing |
| White | Ultra-fine | 8 | Finishing |
This table is one manufacturer’s scheme and is attributed to Komet only. It is a reading aid, not an industry standard.
Regulation and reprocessing
openFDA’s device classification database (checked 2026-10-31) lists two product codes under 21 CFR 872.4535, both Class 1 in the dental specialty:
- DZP, “Instrument, Diamond, Dental.”
- NLD, “Instrument, Diamond, Dental, Reprocessed.” Its definition is the same as DZP except reprocessed, and it states that reprocessing validation data for this device type must be included in a 510(k) submission (70 FR 56911).
On single-use versus reusable, the CDC’s dental infection prevention FAQ on single-use devices (page dated 15 May 2024) defines single-use devices as those “intended for use on one patient during a single procedure,” and says burs, endodontic files and broaches “may be practical to consider single-use” because “the way they are constructed makes them hard to clean.” It adds that cleaning and heat sterilization can lead to deterioration of the cutting surfaces and raise the potential for breakage during patient treatment. Dental burs also appear on the CDC’s list of single-use items that sometimes have reusable, heat-tolerant alternatives. For the general framework, see our guides to medical device reprocessing and autoclavable versus single-use surgical instruments.
Where it matters for clinics and supply decisions
- Read the chart for the brand in hand. Color, grit and micron values come from the manufacturer, so matching colors across brands is not supported by any standard cited on this page.
- Check the regulatory identity. A new bur is product code DZP; a reprocessed one is NLD, and the FDA ties that code to reprocessing validation data.
- Follow the instructions for use and the CDC position on single-use items when deciding whether a given bur is treated as disposable in a practice’s infection-prevention policy.
Related equipment guides: amalgam carrier, crown remover, and the FDA pathway overview in FDA 510(k) premarket notification.
Common misunderstandings
- “Colors are universal.” The chart above is Komet’s; none of the sources cited on this page makes ring colors universal across brands.
- “Class I means no rules.” Class I with 510(k) exemption removes the premarket notification step for the device type; it does not alter the maker’s instructions for use or the CDC guidance on single-use items. Reprocessed burs carry the separate NLD code and its validation-data requirement.
- “The regulation describes every use.” The CFR text states the intended use as smoothing tooth surfaces during the fitting of crowns or bridges; it is a regulatory description, not a clinical guide.
FAQ
What is a diamond bur?
A rotary abrasive instrument with a handpiece shaft and a head that has diamond chips embedded in it (21 CFR 872.4535(a)).
Is a diamond bur an FDA-regulated medical device?
Yes. It is a Class I device under 21 CFR 872.4535, exempt from 510(k) premarket notification, with product codes DZP (new) and NLD (reprocessed).
Do the grit colors mean the same thing on every brand?
No. The table above is Komet’s scheme; ring colors and particle sizes are set by each manufacturer, so check the chart for the brand in hand.
Are burs single-use?
The CDC says burs may be practical to consider single-use because they are hard to clean and cleaning and heat sterilization can deteriorate cutting surfaces. Reprocessed burs exist as a separate FDA product code.
Sources
- 21 CFR 872.4535, Dental diamond instrument: law.cornell.edu/cfr/text/21/872.4535 (checked 2026-10-31)
- openFDA device classification, regulation 872.4535: api.fda.gov (checked 2026-10-31)
- CDC, Single-use devices (Dental Infection Prevention and Control FAQs), 15 May 2024: cdc.gov (checked 2026-10-31)
- Komet USA, A Guide to Dental Instrument Color Codes: Diamonds: kometusa.com (checked 2026-10-31)
