Mistie, I was told not to even THINK about doing anything about missing teeth for a minimum of six months. Implants are very expensive and were not covered by either my dental or medical insurance.
That said, in Portland, I would contact the Oregon Health Sciences University Dental School. When I lived there, I was aware that they took many patients who were without insurance.
Depending upon where the radiation field was, she may need 30 hyperbaric treatments if she is going to have implants. When I was treated, only Providence Hospital in Portland has a Hyperbaric Oxygen Department. I stay in touch with one of the nurses who works there, and I am sure I would have heard if there was another center open. My medical insurance paid for those, and Medicare might also.
You will need the waiting period to explore all these things.
Good luck!