Molars Hurt! Time to replace fillings?

I have 4 molars with silver fillings that are about 12 years old. Two are upper molars and two are bottom.

All 4 of these teeth hurt when I floss them. One upper molar hurts more than the other 3 and it even causes a pulsating sensation in my head sometimes, which I am sure is caused by that tooth.

Do i need to replace all these 4 fillings? Will the dentist clean out whatever is in there before he puts the new fillings in and will that fix it.

I don't think I need a root canal (or maybe just for that one that is pulsating), these teeth hurt when flossing, but there isnt much pain usually.

[Jerome Tsang, DDS]

It could be the fillings fault or it could be the gums.  You need to go to a dentist to figure out which is which and get the proper treatment.  You may just need a cleaning.