Repairing dents or scratches in finished metal sculptures requires a careful approach to preserve the artwork's integrity. Here are the most effective methods:

1. Assess the Damage: Begin by evaluating the extent of the dent or scratch. Minor surface scratches may only need polishing, while deeper dents might require filling or reshaping.

2. Polishing and Buffing: For light scratches, use fine-grit sandpaper (600-2000 grit) followed by a polishing compound. Buff the area with a soft cloth or rotary tool to restore shine.

3. Filling Dents: For deeper dents, apply a metal filler or epoxy designed for sculptures. Smooth the filler, let it cure, and sand it flush with the surrounding surface.

4. Cold Metalworking: Small dents can often be gently hammered out from the reverse side using a rubber mallet or specialized dent removal tools.

5. Professional Restoration: For valuable or intricate sculptures, consult a professional restorer who can use advanced techniques like welding or metal retexturing.

Always finish by reapplying protective coatings like wax or clear lacquer to prevent future damage. With patience and the right tools, most metal sculptures can be restored to their original beauty.