My husband had his original surgery in 1975 he was 29 they removed part of the roof of his mouth and performed a modified radical neck for the lymph nodes. Had full radiation dose at that time. Due to his age they didn't pull his teeth. Over several years, problems developed infections etc. due to the rad. in 1990 it was decided to pull all the remaining teeth. He was set up for 20 hyperbaric treatments to prepare for the surgery and then 20 more following surgery. everything went very well, no discomfort during the dives. It made a big difference in his preparation and his healing.