Dave, since John's teeth were pulled, I can't address the cavity issue- But, I would have her Dentist write a report to the effect that radiation has caused serious problems with her teeth that need to be addressed before the condition deteriorates further. Jerry might help with the wording. Then I would call her Ins. Co. and speak to them in technical terms and tell them you have this report and need to know who to send it to.Have you had any success with her other issues? Amy