To locate the cutting edge of a Gracey 1/2 outside the mouth, which orientation is correct?

• A. The inner edge when the shank is parallel to the floor
• B. The upper edge when the terminal shank is perpendicular to the floor
• C. The lower edge when the terminal shank is perpendicular to the floor
• D. The outer edge when the blade is horizontal

Answer: (C)

The key idea is using the correct cutting edge of a Gracey curet and how the blade sits relative to the tooth when working outside the mouth. For Gracey 1/2 on anterior surfaces, the active cutting edge is the lower edge. When the terminal shank is perpendicular to the floor, that lower edge lines up with the tooth surface and becomes the edge that engages calculus for effective removal. This orientation provides the correct angulation and prevents damage to the gingiva that can occur if a different edge or an incorrect shank position is used. Using any other edge or a different shank orientation would place the wrong edge against the tooth, making calculus removal inefficient and increasing the risk of tissue trauma.