Brian,
My mom is having trouble eating after radiation. Part of this is that her mouth is going through change after change. But I always see her opening her mouth like her jaw hurts. Are there ways I can inquire to her about what is going on? I am wondering if her jaw is experiencing what you described above? I am a physical therapist so I am aware of the affects of not using your range of motion. Any good questions I could ask her to get at the potential problem would help. I want to stay away from asking her about her tongue and inside of her mouth, as I already know this is a problem. Thanks.