Scaler or Curette? Differences and Use in Periodontics
At first glance, scalers and curettes look alike: a handle, an angled shank and a narrow working end with cutting edges. In detail, however, they differ clearly, and these differences determine where an instrument can be used. This guide explains the difference between scaler and curette, compares the sickle scaler, universal curette and Gracey curette, covers the Columbia and Langer universal curettes and summarises the basics of sharpening.
Key points at a glance
- A sickle scaler has a triangular cross-section, a pointed tip and two cutting edges. It is intended for supragingival calculus.
- A curette has a semicircular cross-section with a rounded back and a rounded toe. This allows it to work subgingivally in the pocket as well.
- On universal curettes, the face is at a right angle to the lower shank and both cutting edges are active. One instrument reaches many tooth surfaces.
- Gracey curettes are area-specific: the face is tilted relative to the lower shank, and only one cutting edge is used.
- Langer curettes combine a universal blade with the shank designs of the Gracey curettes.
- Dull instruments work less effectively and tire the hand. Sharpening must preserve the original shape of the working end.
Scaler and curette: the basic difference
The difference lies in the shape of the working end. On a sickle scaler, two cutting edges meet at a point, and the back is pointed as well. In cross-section this forms a triangle. This shape is sturdy and well suited to removing heavy deposits on the crown and just below the gingival margin, for example in the interproximal spaces of the anterior teeth.
On a curette, the back and toe are rounded. The cross-section is semicircular. The rounded shape protects the soft tissue when the instrument is inserted into the gingival pocket. Curettes are therefore used both supragingivally and subgingivally, including for removing calculus from the root surface.
This leads to the most important rule: sickle scalers do not belong in the pocket. Their pointed tip and sharp back can injure the junctional epithelium and damage the root surface.
Universal curette or Gracey curette?
Within the curettes there are two design principles.
Universal curettes
On a universal curette, the face is at an angle of 90 degrees to the lower (terminal) shank. Both lateral cutting edges are sharpened and can be used. A double-ended instrument can therefore treat many surfaces in the anterior and posterior region. The clinician sets the correct working angle to the tooth surface by tilting the instrument. Well-known universal curettes are the Columbia curettes (for example 13/14), Barnhart and Younger-Good.
Gracey curettes
Gracey curettes are area-specific. The face is tilted at about 70 degrees to the lower shank (“offset blade”). Only one cutting edge is used, the longer, lower one. Each number is designed for specific teeth and surfaces, for example the Gracey curette 11/12 for mesial and the Gracey curette 13/14 for distal surfaces in the posterior region. A detailed overview of all numbers can be found in our guide What are Gracey curettes and what models are there?.
Langer curettes
Langer curettes combine both principles: they have a universal blade with two cutting edges and 90 degrees to the shank, but the shank designs of the Gracey curettes. They were originally designed as a set of three instruments: Langer 1/2 for the mandibular posterior teeth, Langer 3/4 for the maxillary posterior teeth and Langer 5/6 for anterior teeth and premolars. The 17/18, among others, was added later. Because both cutting edges are active, a Langer curette reaches mesial and distal surfaces with the same working end.
Comparison: sickle scaler, universal curette, Gracey curette
| Feature | Sickle scaler | Universal curette | Gracey curette |
|---|---|---|---|
| Cross-section | Triangular | Semicircular | Semicircular |
| Tip | Pointed | Rounded | Rounded |
| Back | Pointed | Rounded | Rounded |
| Face to lower shank | 90° | 90° | approx. 70° (tilted) |
| Active cutting edges | Two | Two | One |
| Area of use | Supragingival | Supra- and subgingival | Supra- and subgingival, especially deep pockets |
| Tooth surfaces | Mainly interproximal spaces, crown | Many surfaces with one instrument | Area-specific per number |
| Examples | H6/H7, 204S | Columbia 13/14, Barnhart, Langer | Gracey 1/2 to 17/18 |
Which instrument when?
In practice, the instruments complement each other. Sickle scalers are suitable for heavy supragingival calculus, especially on anterior teeth. Universal curettes cover many surfaces with few instruments and are used supra- and subgingivally. Gracey curettes show their strength in deeper pockets and on the root surface, because their shape is adapted to specific tooth surfaces. For furcations and narrow, deep pockets there are variants with a shorter working end such as the Mini Gracey curette 11/12 or with an extended shank such as the After Five Gracey curette 11/12.
If you are building up a basic set, you can start with a kit, for example the Gracey curette set of 9 or the Gracey set of 6 instruments. You will find all curettes in the chisels and curettes category and further instruments in the periodontics category.
Sharpening basics
Scalers and curettes become dull over time. A dull instrument slides over the calculus instead of removing it, requires more force and tires the hand. Some basic rules:
- Test sharpness: Place the cutting edge at the working angle against a plastic test stick. A sharp edge catches, a dull edge slides. Test the heel, middle and toe of the cutting edge.
- Keep the angle: An angle of about 70 to 80 degrees between face and sharpening stone is common. This preserves the original edge geometry.
- Preserve the shape: On curettes, the toe and back must remain rounded. On Gracey curettes, only the working cutting edge is sharpened.
- Stone and lubricant: Fine stones produce a smoother, longer-lasting edge. Synthetic stones are usually used with water, natural Arkansas stones with oil.
- Hygiene: Sharpening stone and test stick are cleaned and sterilised after use.
Every sharpening removes material. A working end that has become noticeably thinner is at risk of breaking and should be replaced. Advice on cleaning and sterilisation can be found in our guide to instrument care and reprocessing.
Frequently asked questions
What is the difference between a scaler and a curette?
The sickle scaler has a triangular cross-section and a pointed tip. It is intended for supragingival calculus. The curette has a semicircular cross-section with a rounded toe and can also be used subgingivally in the pocket.
Can a sickle scaler be used subgingivally?
No. The pointed tip and pointed back can injure the soft tissue and the root surface. Curettes are intended for subgingival work.
What is a universal curette?
A curette whose face is at a right angle to the lower shank and whose two cutting edges are both active. It can be used on many tooth surfaces. A well-known example is the Columbia 13/14.
How do Langer and Gracey curettes differ?
Both have similar shank designs. However, the Langer curette has a universal blade with two active cutting edges, while the Gracey curette has a tilted blade with only one working edge.
How often do curettes need to be sharpened?
That depends on use and the amount of calculus. Check sharpness regularly with a test stick and sharpen as soon as the edge no longer catches.