Pink spots in mouth

My 10year old GSD has pink pigments spots appearing on her lips/jowl - is this anything i should worry about?

She did have lip fold dermatitis a few weeks ago which turned part of the jowl pink but that has gone back to black again after a course of antibiotics. I don't recall seeing these pink spots before, I thought her mouth was all black, what can it be? If anyone has experience in this I would be grateful to hear from you.