Hygiene Atlas

Atlas · Plate XI · Instrumentation · 06

Sickles and curettes

Sickles have a triangular cross-section and a pointed tip, so they stay supragingival. Universal curettes have a rounded toe, a face at 90 degrees to the lower shank and two cutting edges that serve the whole mouth. Gracey curettes have a tilted face and use only the lower edge, and they are numbered by area: 11/12 for posterior mesials, 13/14 for posterior distals.

High-yield facts · 8

  1. Sickle scalers: triangular cross-section, pointed tip, two cutting edges, face at 90 degrees to the lower shank; supragingival only.T3
  2. Anterior sickles have straight shanks; posterior sickles (e.g., H6/H7, 204S) have contra-angled shanks.T3
  3. Universal curettes: semicircular cross-section, rounded toe, two parallel cutting edges, face at 90 degrees to the lower shank; one double-ended instrument covers the whole mouth.T3
  4. Area-specific (Gracey) curettes: face tilted 60-70 degrees to the lower shank, one cutting edge per end (the lower, longer, outer edge), curved blade.T3S59
  5. Gracey 1/2, 3/4: anteriors. 5/6: anteriors and premolars. 7/8, 9/10: posterior facial and lingual. 11/12: posterior mesial. 13/14: posterior distal. 15/16: posterior mesial (modified 11/12 shank). 17/18: posterior distal (modified 13/14 shank).T3S59
  6. Extended-shank (after five) Graceys have a 3 mm longer lower shank for pockets over 5 mm; mini-bladed versions have a blade half as long for narrow pockets and furcations.T3
  7. Langer curettes combine a universal blade (both edges cut) with Gracey shanks (5/6, 11/12, 13/14 shank designs).T3
  8. The cutting edge is the line where the face meets the lateral surface.T3

Facts are written in our own words; each tag links to its source. Values marked "sources vary" differ between references, so check the one your program uses.