I hate to add to your confusion and debated whether to post, but feel I must comment about the rad oncologist's response to your husband about dental questions. It is correct that teeth are no longer routinely removed prior to rad therapy. However, saying it can be taken care of down the road is not good advice (unless delaying rad therapy is inadvisable.) However, I do not see that that reason was given. Any dental restoration that can be done prior to treatment should be considered. It's not just extractions as Paul explained.

Were you not advised to have a comprehensive dental evaluation with teeth mapping and fluoride trays made? Only then can an educated decision be made about any dental problems. It's important to see a dentist knowledgable about oral cancer, which is difficult outside of a CCC. It's overwhelming, I know and sorry you have to deal with this.