First of all, how deep are the dents? Have they scratched the finish off the harp, or are they just “skin-deep”? There may be a method to correct them if it is the latter case. I can’t tell you the exact method, as it was only mentioned to me once by a luthier, but it had something to do with steam?? And since I am not sure what type of finish you have, I even hesitate to suggest this. Perhaps call a professional harp maker, or maybe Carl can jump in here with a more experienced response….