If you have dents in the metal-clad doors in your home, one answer is to use auto-body fillers to make the fix. Either the polyester resin or fiberglass paste fillers bond well with steel, and the repair can be made like on a car. But, because you can finish the door with acrylic-latex trim paint, not glossy auto body paint, you don’t need the skills of an auto body technician to get excellent results.