There are dozens of composites to choose from....do your research first. I recently had 2 of my 5 replaced with a composit called Heliomolar. I then discovered that it has high percentages of BISGMA which is not good and it has Flouride...also not good. But I also discovered that they ALL have certain levels of BISGMA and other chemicals that have been linked to cancer. Some of them do not have floride. Diamond Crown is all the rage. There is not a whole lot of info on them out there, but the little I've found looks good. Its main ingrediant is PEX which, I discovered last night has also been linked to Cancer. But they seem like the lesser of all evils, so I have requested my dentist to replace the remaining 3 with this material. And a bunch of people on here have had this material and say good things about it. Bottom line is any of these are proabably less toxic then mercury and you can only go with the avaliable information. Good luck. By the way.....what State do you work for. I am a state employee too, and my dental reimbursement for this is still to be determined.