Any picture helps - you can put a circle around the old abscess. It will help us to be able to tell you if it's something like a sticker orbug bite that you just need to make sure it's cleaned out or a tooth abscess that might come back.
not that we can tell everything from a photo but it can help.
also, if it was from something like a bee sting, splinter, sticker, something, you need to make sure that piece of debris is out of the abscess hole or the abscess will come back.