donfoo,
As you already know, dental extractions post-radiation therapy are a risk due to the possibility of developing ORN (osteoradionecrosis) resulting from compromised blood flow to the jaw. My past posts on this topic, document the bad advice that was offered by various dental specialists in our local area. My husband did not get good advice until he consulted a dental surgeon who was part of an oral cancer team at a large NYC hospital.

The OCF pages under dental issues are helpful.
All the best,
travelottie