Which principle is specifically about shaping and smoothing margins to achieve a clean finish?

• A. Debridement
• B. Outline form
• C. Finishing
• D. Convenience form

Answer: (C)

Finishing focuses on shaping and smoothing margins to achieve a clean finish. After the cavity is prepared, this step refines the cavosurface margins and walls, removing any irregularities and sharp angles so the margin is smooth, continuous, and well-adapted to the tooth. A clean, well-finished margin is essential for a proper seal with the restorative material, reducing the risk of microleakage and plaque accumulation and allowing the amalgam to be condensed effectively. This principle is distinct from debridement, which is about cleaning away carious tissue and debris; outline form, which defines the overall shape and extent of the cavity; and convenience form, which makes the preparation easier to access and restore.