Regarding teeth, the woman who did the highest ever handglide off the bottom of a balloon at 30k + feet in Saudi or somewhere similar, had her fillings redrilled, so that air gaps expanding did not explode and cause her massive pain. In this respect, it probably is possible that decompression can cause pain from fillings, however, it was I think only a minor risk they said on the programme, from older fillings?
Oh, and my ears can do that as well, ond only at the end of a cold do they tend to need 'blowing' against the nose to equalise the pressure.