Possible Rot On-top Of Shell?

[BunnyFilms]

Hello! I have a three-toed box turtle and when I adopted her, she had this "rot" on the top of her shell. I am concerned because after owning her for a year, it has shown no signs of healing. Does this classify as shell rot? How do I treat it and could it develop into something life threatening?

 

[ZEROPILOT]

No
It's some other type of older injury.
It's only a cosmetic concern

 

[Yvonne G]

Not shell rot, but an old, healed injury.