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General product and regulatory information only; this page is not medical or clinical advice.
Short answer
A dental scaler is an instrument used to remove calculus (hardened deposits) from teeth. In U.S. regulation there are two distinct kinds: a hand-held periodontic scaler, which FDA treats as a Class I dental hand instrument, and an ultrasonic scaler, which FDA classifies as a Class II device that uses a vibrating tip.
Definition and scope
The term covers more than one device family, and the U.S. Code of Federal Regulations (21 CFR Part 872, dental devices) defines them separately. Which regulation applies depends on how the scaler works, not on what it is called in a catalogue.
- Ultrasonic scaler. 21 CFR 872.4850 defines it as a device intended for use during dental cleaning and periodontal (gum) therapy to remove calculus deposits from teeth by application of an ultrasonic vibrating scaler tip to the teeth.
- Hand scaler. A “periodontic scaler” is named among the instruments covered by 21 CFR 872.4565, which defines a dental hand instrument as a hand-held device intended to perform various tasks in general dentistry and oral surgery procedures.
The same regulation also names probes, curettes and a “hand instrument for calculus removal” among dental hand instruments. For the examining instruments that often sit alongside scalers on a tray, see dental explorer types and periodontal probe types, markings and FDA class.
How scalers are used in practice
The only use stated in the ultrasonic scaler regulation is calculus removal during dental cleaning and periodontal therapy, by applying the vibrating tip to the teeth. The hand instrument regulation is deliberately broad (“various tasks”) and does not describe a single technique. Clinical use is a matter for trained dental professionals and the manufacturer’s instructions for use.
One practical point comes from infection control rather than technique. The CDC’s Guidelines for Infection Control in Dental Health-Care Settings (2003) names ultrasonic scalers, alongside handpieces, as rotary or powered instruments whose use produces spray. That spray can contain aerosols, which the CDC defines as particles of respirable size (under 10 µm); the same guideline notes that spatter travels only a short distance and settles out quickly.
Hand and ultrasonic scalers compared by regulation
The table below compares the two families using only what the two regulations state. It is a regulatory cross-walk, not a ranking or a recommendation.
| Point of comparison | Hand (periodontic) scaler | Ultrasonic scaler |
|---|---|---|
| Regulation | 21 CFR 872.4565, dental hand instrument | 21 CFR 872.4850, ultrasonic scaler |
| FDA classification | Class I (general controls) | Class II |
| How it is described | Hand-held device for various tasks in general dentistry and oral surgery | Device that removes calculus with an ultrasonic vibrating scaler tip |
Class I means general controls apply (the hand-instrument regulation also exempts it from premarket notification if made of the same materials used before May 28, 1976, subject to 21 CFR 872.9). The regulation text for the ultrasonic scaler places it in Class II. To see how FDA device classes fit together, read what is a medical device and the dictionary entry on the Medical Device Amendments of 1976, which is the origin of the May 28, 1976 date in the exemption.
Where it matters for labs, clinics and supply decisions
Two sourced points matter when a clinic, lab or supply team handles scalers.
- Classification differs by type. Because a hand scaler and an ultrasonic scaler fall under different regulations and classes, a product listing should be matched to the right one before it is compared with another.
- Reprocessing follows the item’s risk category. The CDC guideline describes semicritical items as those that touch mucous membranes or nonintact skin and carry a lower risk of transmission, and notes that the majority of semicritical items in dentistry are heat-tolerant, which is why it calls for heat sterilization. Which category and which reprocessing method apply to a specific scaler or tip is set out in that manufacturer’s instructions for use.
Checklist: what to confirm in the manufacturer’s labelling
These are items to find in the labelling or instructions for use for any scaler.
- Whether the device is described as a hand instrument or an ultrasonic scaler, and the FDA classification it is marketed under.
- The reprocessing method the manufacturer specifies for the instrument or tip, including whether heat sterilization is supported.
- Which tips or inserts the manufacturer lists as compatible with the handpiece or unit.
- Whether the item is supplied sterile or non-sterile (see sterile vs. non-sterile classification).
Common misunderstandings
- “A scaler is one device type.” In U.S. regulation it is at least two, with different classes.
- “Ultrasonic scalers create no aerosol.” The CDC names ultrasonic scalers as a source of spray that can contain aerosols under 10 µm.
- “Class I means no rules.” Class I devices are subject to general controls; the premarket notification exemption here is conditional on materials and limited by 21 CFR 872.9.
FAQ
What is a dental scaler used for?
For the ultrasonic type, FDA’s regulation states the use as removing calculus deposits from teeth during dental cleaning and periodontal (gum) therapy.
How does FDA classify a dental scaler?
A hand periodontic scaler is covered as a Class I dental hand instrument (21 CFR 872.4565); an ultrasonic scaler is Class II (21 CFR 872.4850).
Do ultrasonic scalers produce aerosols?
The CDC lists ultrasonic scalers among instruments whose use produces spray, which may contain aerosols of respirable size (under 10 µm).
Sources
- U.S. FDA regulation, 21 CFR 872.4850, Ultrasonic scaler (checked 2026-10-30).
- U.S. FDA regulation, 21 CFR 872.4565, Dental hand instrument (checked 2026-10-30).
- CDC, Guidelines for Infection Control in Dental Health-Care Settings, 2003, MMWR 52(RR-17) (checked 2026-10-30).
