Pain in filling whilst spearfishing...

Sounds to me like the dentist left a little air trapped in the hole in your tooth when he put the filling. This will cause the pain when you dive and as far as I know there's no way of stopping it unless you get the filling taken out and put in again.

I was very explicit with my dentist when I had my fillings put in that I was a diver and could not have any airspaces in my fillings. I've had no troubles with them and i've taken them fairly deep. One came out but he replaced it and I had no troubles.

Also, if you have a little infection or the hole isn't cleaned/drilled out properly then some gas can build up which would have the same result.

I would contact your dentist and tell him that there must be some air trapped in the filling and ask if it's possible to have it replaced. They should do it (and for free too) because I imagine there would be ramifications for flying as well, and in my opinion they didn't doo the job right in the first place if there's air in it.

Unfortunately these sorts of problems don't go away by themselves - a replacement filling is pretty much your only option.

Cheers,
Ben

As Benny says but since but also you might get away with pushing it untill the surrounding tissue of the cavity/airspace bursts filling the cavity/air pocket with blood and instant relief(you hope). Any gas will be removed and the cavity eventually filled with tissue.....great choice to have to make I would want to be getting payed to make that one!

Well that brings a tear to the eye....