Skin graft or fat fillers to hide my sacral dimple for a more aesthetically pleasing look? (photos)

I was born with a sacral dimple and a birth mark on the bottom of my back and just above the crease of my bottom. I have had no physical problems related to this all my life. These make me feel very self-conscious though. I am considering cosmetic surgery, but need to know what procedures would be involved so I can work out the costs. What do you think? Would a skin graft or fillers be enough? Thank you.