Not sure about fixing it but being aware and conscious of it has helped and not pushing it by chewing gum :)

Yes it increases when my TMJ acts up. It is common with TMJ. I did not know about with MS. I have mentioned it and asked questions of my Neurologist who denied any connection. It was one of my goals after surgery joint construction in Physical Therapy. Wondering if it possible to fix it?

This has happened to me in the past and partially why I no longer chew gum

It was happening to me pretty regularly but I'm more careful now.

Yes but now you know the pain that can happen. I'm willing to bet you take steps to reduce biting your lips, tongue and cheek