What preparation step is the refinement of cavity walls and margins for optimal restoration?

• A. Finishing
• B. Caries removal
• C. Isolation
• D. Occlusion adjustment

Answer: (A)

Refining the prepared cavity involves shaping and smoothing the walls and margins so the restoration seats firmly and seals well. This finishing step removes any irregularities, sharp angles, and overhangs, giving clean, smooth margins that match the tooth structure. A well-finished cavity helps the restorative material adapt closely to the walls, reduces stress concentrations at the margins, and promotes a durable, esthetic seal. The other steps focus on removing decay, keeping the field dry, or adjusting the bite after placement, which don’t describe refining the cavity walls and margins for optimal restoration.