How to Remove Callous-like Scar on Lower Lip

I have a scar on my lower lip. It's hard (callous-like) and I pick at it with my teeth. I believe that it started out as a cold sore. The dermatologist biopsied it (it's fine) and now I can't get rid of it (especially since I keep picking at it). It's a catch 22. Any advice you can offer would be greatly appreciated. Thank you.