I had six cavitites in betweem my lower molars about 7 years ago after not going to the dentist for a few years. I have gone every six months ever since. I floss every day, use high flouride toothpaste and brush. My gums are in excellent shape. My dentist filled all of the cavitiies with composite fillings. It seems as though every time I have x-rays, it shows new decay forming under ALL of them! I had new decay under two teeth one year ago and the dentist refilled them and said they should be fine. Now, one year later, I have decay so large under the same tooth,I now need a root canal! Now they are all failing again. Is this the fault of the dentist? I have 2 amalgam fillings that are over 20 years old that are fine.I'm so disappointed in my dentist. I plan to have a root canal done and a crown, but what is my solution for the other failing fillings? Thank-You.