Sometimes steam or water can remove dents in wood but I need more information before I make a suggestion. Is the floor 'tiles' or wood blocks? Has it got a varnish or wax finish? How old is it? and What is the sub floor? PLEASE DON'T TRY WATER OR STEAM YET!
If you can answer the questions first I'll try and help.
I had the same problem. My floor is 4mm oak laminated onto a ply base. It comes factory vanished. The sub-floor is floor-boards with a flexi self level floor screed on top. Any help would be appreciated.