The visual impact of a dent can be minimised by localised application of water and heat. A damp rag should be placed over the dent, and a clothes iron is used to apply heat to the area. This effectively steams the timber fibres and causes them to expand back into their original position. Care must be taken not to damage the surrounding timber floor.
If the steaming method doesn't work, applying a timber putty in a similar colour to the floor is the next best thing. For minor scratches and damage, consider a Timbermate Timber Touch-Up Kit. These are wax sticks that can be melted to fill voids and scratches. - MitchellMc