When the terminal shank of a Gracey curette is perpendicular to the floor, what is the appearance of the cutting edge?

When the terminal shank of a Gracey curette is perpendicular to the floor, the cutting edge of the instrument slopes towards the floor. This design is a fundamental characteristic of Gracey curettes, which are specifically angled to ensure effective scaling and root planing in periodontal therapy.

As the handle is positioned vertically and the terminal shank is perpendicular to the treatment area, the cutting edge aligns in a way that optimizes its engagement with the tooth surface. This angling allows for better adaptation to the root surfaces, facilitating the removal of calculus and diseased tissue.

The design of the Gracey curette, including the angle and curvature of the blade, is intended for specific areas in the mouth. When the terminal shank is oriented properly, the cutting edge's slope ensures that the active part of the instrument contacts the surface effectively, enhancing the clinician's ability to perform thorough periodontal debridement.

Understanding this concept is crucial for proper technique and effective treatment outcomes in periodontal care.