Dents and also scratches happen to hardwood floors often. High heels are torture to hardwood floors. Over time any furniture legs can dent or scratch the floors. It might be an idea to add some area rugs under your furniture or there are also felts available that go directly under the furniture legs. Also you could add some area rugs to the highly traveled areas in your home such as kitchens, hallways, in front of the couch.
There are some people that feel that the scratches and the dents give their hardwood floors character, when your kid thinks he plays for the sounders fc and kicks the soccer ball on the hardwoods. But when you feel that you are in fact sick of them you can get your hardwood flooring refinished. If you have your hardwood floors refinished every decade or so and keep on top of protecting your hardwood floors, they will look the best. Everything you do from moving furniture to allowing your dog to roam in the house will affect your hardwood floors.