The cyst on the mandible can sometimes heal over time. As I understand it has only been less than a year out of radiotherapy treatment. The mandible can be injured from the radiation and in some cases die (osteoradionecrosis) however this awful side effect from treatment can also be repaired if it comes to that. An oral surgeon should be able to make a determination however time will give you an indication of either improvement or not.
As for the lung nodules, don’t lose too much sleep over this as often as not these prove to be nothing even after a lung biopsy, which is rather like a bad day at the amusement park. Can you let me know how your repeat CT turns out?
Also if your jaw issues progress, could you keep me updated as well?
Just to remind you, your post cancer recovery often takes two or more years and beyond for some effects to work themselves out.