Hello, I just wanted to say I am sorry about your little hedgie. There are a couple of different things that it could be. Sometimes a benign growth can form called gingival hyperplasia. The other scenario is it could be an oral tumor that are very common in hedgehogs. It is not anything that you did or did not do and there is really nothing you can to do prevent either of these. You can take her back to the vet to get an x-ray and see if the jaw is involved and if it is not cancer you can possibly have it removed, or debulked. They can also remove the loose teeth and put her on some antibiotics. Other than that, it is good she is already on some medicine for pain. I suggest you feed her wet kibble or soft food. You can wait and see if the tumor grows, or if she will not eat even with the soft foods then it may be time to say goodbye. I have had a couple of hedgies that this happened to. Best of luck to you whatever you end up deciding to do, she knows she is loved, I am sure.