Red Eared Tortoise opens and closes mouth

by Linda
(Kuala Lumpur, Malaysia)

Hi there, my tortoise currently has MBD (it's still a very young one) but then I believe it's situation is improving right now as it's eating better and does not sleep that much. My questions are:

1) How do I determine if the situation has improved? will it's shell turn green back?

2) Why does it open and close its mouth?

Thank you.

Regards,
Linda