Yes horses teeth need floated once a year. Sometimes twice depending on the horse.
I would get her teeth done ASAP. My gelding's teeth had never been floated until I got him, but his previous owner still rode him in a bit. Now (even though his teeth have been floated twice, and he has no other problems with them), he absolutely hates bits. It doesn't matter what kind it is, or who's riding him, he will not put up with it at all.
I'm not saying this will happen to your horse. Just sharing an experience to a similar situation.
I personally wouldn't try bridling her again until her teeth get floated.
"Saving one horse won't change the world, but it will change the world for that one horse."