Okay so I used to have braces for 4.5 years, and I’d get these ridge, bumpy lines along my cheeks in my mouth usually where my upper and lower teeth meet. Oddly, I’ve been pushin forward a lot more (because I haven’t got a lot of results from forward growth) and there’s these same lines again? Is this an indicator that our teeth are moving like when I had braces that shifted them or another explanation I haven’t thought about? I tried finding the term for them to no avail :(
The ridges are probably where the cheeks get caught between the teeth no? And if you stopped getting them but get them again now, your teeth may have moved. Are you pushing with your tongue or using an expander?
Just tongue :) Focused on front
I used to traumatically bite my cheeks, especially while rushing to eat, and got painful canker sores on almost a monthly basis. Since correcting my tongue posture following your advice, this problem has resolved. I believe my upper arch has expanded slightly, but enough to hold the cheek curtain away from the bite surface. Can I expect that the protruding linea alba on my buccal mucosa will recede in time? I think they might feel less prominent already.
I submitted this question about the "linea alba" ridges on my cheeks in the thread for Dr. Mew's Q/A video, but it wasn't selected. I think you are wondering about the same thing. My understanding is that these ridges appear, as @fpquestions suggests, from the buccal mucosa getting caught between the teeth. To prevent these, the upper or lower arch needs to be wider than the opposite arch so that the outer cusps hold the cheek curtains away from the incisal surfaces. So it could be that as you are expanding your upper arch with your tongue posture, it is becoming approximately the same width as the lower arch such that neither arch is holding the cheek out of the way. As your maxillary arch continues to expand, it should become wider than the mandibular arch and then I think these callused ridges on the inside of the cheeks should gradually recede. When I look and feel inside my cheeks now, I notice my parotid duct orifice protruding slightly higher than the biting surface, but most of the lower ridge from biting my cheeks has gone away.
Linea Alba:

Parotid Duct Orifice:
