This process may have to be repeated several times. Scrape away blackened area with steel wool, razor or knife. Shallow burns will fill in with finishing. For deeper burns, fill with a mixture of wood glue and sanding dust. Put the mixture in, let cure, smooth with a razor blade.
Dents are the results of wood fibers being crushed and compressed.
To raise a dent, simply swell the fibers back up with moisture in the form of steam. Place a damp cloth over the dent and hold a medium-hot iron on it. Check progress frequently. When veneer begins to stick, apply pressure until glue dries. If no sticking occurs, regluing is needed.