I'm a member of her fan club and she talks to us a lot... I'm pretty sure she hasn't had anything done. I don't see any change in her looks, but the picture of her in the red/pink striped dress is awful. She doesn't actually look like that.
As for the teeth, well, in all her child hood pictures she has perfect, gorgeous, white teeth, and that includes her in her 18s. And considering what her child hood was like, she didn't have any work done in Broken Arrow, OK, trust me.