pages 704-705 curets

Types of curets

A. Universal Curets

  • Adaptable for supra- and subgingival instrumentation on any tooth surface; ideal for removing large deposits quickly across multiple teeth.

  • Working ends: paired mirror images on a double-ended instrument.

  • Face is perpendicular to the lower shank: 90degree90^{degree} .

  • Cutting edges: two per working end; edges are parallel and level with each other; both edges used; blade sharpened on both sides and around the toe.

B. Area-Specific Curets

  • Designed for adaptation to specific surfaces; ideal for fine scaling and root debridement.

  • Working ends: paired mirror image on a double-ended instrument; typical pairs include 1/2, 3/4, 5/6, 7/8, 9/10, 11/12, 13/14, 15/16, 17/18 (Gracey series).

  • Face is approximately 70degree70^{degree} to the lower shank to create an offset blade.

  • Cutting edge: one working lower cutting edge per working end; the working edge is the lower edge when the handle is vertical.

  • Blade sharpened on one side (lower edge) and around the toe.

C. Advanced Area-Specific Curets

  • Variations provide greater opportunities for advanced instrumentation: deep pockets, curved root surfaces with moderate-to-severe attachment loss, furcations on multirooted teeth.

  • Terminal shank can vary in length and thickness; blade can vary in length and width.

  • After-five curet: extterminalshank=3 extmmextlongerext{terminal shank} = 3~ ext{mm} ext{ longer}; blade width =0.9imesextstandard= 0.9 imes ext{standard}; improves access beyond 5 extmm5~ ext{mm} pockets.

  • Mini-five curet: extterminalshank=3 extmmextlongerext{terminal shank} = 3~ ext{mm} ext{ longer}; blade width =0.9imesextstandard= 0.9 imes ext{standard}; blade length =0.5imesextstandard= 0.5 imes ext{standard}; shorter blade facilitates adaptation to curved root morphology including concavities, depressions on proximal surfaces, root surfaces within furcations, and interradicular convexities.

  • Micro-mini five curet: terminal shank =3 extmmextlongerandthicker= 3~ ext{mm} ext{ longer and thicker}; blade width =0.8imesextmini−fivewidth= 0.8 imes ext{mini-five width}; blade length =0.5imesextstandard= 0.5 imes ext{standard}; longer, more rigid shank with a narrower and shorter blade enables greater lateral pressure for deep, tenacious calculus deposits.

Curet-Specific Instrumentation

  • Adaptation: toe-third of the cutting edge remains on the tooth surface at all times; for line angles, only the terminal 1−2 extmm1-2~ ext{mm} of the toe may be used.

  • Edge adaptation rules:

    • Either cutting edge of a universal curet may be adapted on a tooth surface.

    • Only the lower cutting edge of an area-specific curet may be adapted.

  • Angulation: blade face-to-tooth angle varies with action; supragingival approx. 70extextdegree70^ ext{ extdegree}; subgingival insertion: blade closed with face-to-tooth angle 0extextdegree0^ ext{ extdegree}; subgingival deposits removal: blade opened with face-to-tooth angle 70extextdegree70^ ext{ extdegree}.

  • Activation: light assessment strokes, moderate root debridement strokes, and heavy calculus removal strokes.

Periodontal Files

  • Working Files: includes stainless steel Hirshfeld and Orban files.

  • Uses:

    • Crushes and fractures heavy calculus into fragments prior to use of curets.

    • Removes burnished calculus impervious to removal with other bladed instruments.

    • Removes gross deposits on patients for whom ultrasonic use is contraindicated.

  • Instrument Design:

    • Multiple cutting edges lined up as a series of miniature hoes on a round, oval, or rectangular base.

    • The metal blades are at 90extextdegree90^ ext{ extdegree} to the shank.

    • Reduced tactile sensitivity because of the series of blades.

    • Shanks are variously angulated; most are paired.