My dentist thinks it is just as well to do some diving, so the
marginally loose fillings will go rather that seep in contaminants
over time and make a bad infection.

Of course, the dentist gets to do the work.

-- mrr

Ditto that - covered in our NAUII books aswell - "dental sqeeze". When I had
taken my course, many years ago, I had asked my dentist about it. He himself
has noted of it. Caused by improper packing of the filling material in the
tooth cavity. From there, the little air bubbles do their work as we dive.
If it was work done at his office, he repairs no charge, but he has seen
very few cases himself.

The other cause of dental fractures is teeth grinding. I do it in my sleep
and had a dental night guard fitted to prevent it on the advice of my
dentist. In use for the past year and noticeable reduction in crack and
chips.

Also, no more cracking lobster or crab parts with my teeth - have to be
civilized now - oooooo ;P