dental problem...need advice

Dear message boards,
I know this is probably not a malpractice case after reading some other dental messages below, but I would like to get some legal advice. In February, a dentist changed a filling from a "metal" to a tooth colored filling because he said they were harmful. The "metal" filling was not causing any problem what so ever, no pain, no nothing. Then thoughout March, he kept filing the filling down, because I kept complaining about tooth pain when I applied any sort of pressure on the tooth. In April, he then changed the filling with a temporary "drug" filling, to sooth the pain. Then now in June, he put in another tooth colored filling and also filed down the filling. To this day, I have not been able to eat properly on the right side of my mouth since February. I have now had 3 fillings put in and still have the tooth pain and am afraid now I may need a root canal. What should I do? I have lost confidence in this dentist and feel like he has caused this.
Thanks.
Dave