Teeth Problems Underwater

[davsholm423]

Hello, this fall my brother, dad, and I are planning on taking the step to become certifed after doing a few resort courses on past vacations. My brother has done two resort courses before, and on the most recent one he had some problems with his teeth. After starting our descent from the boat his teeth immediatly started hurting and at one point felt like they were going to literally fall out. This dive was just to about 30 feet. His teeth problem completely took the fun out of his dive and made him a little leary with wanting to dive again. Does anyone know what would cause this pain in and around his teeth? Is it common and easily treatable?

Thanks a lot