Tooth sensitivity months after filling done (got it replaced still persisting)

[kittyplays]

Hello, my problems started after I got replaced my amalgam filling (for esthetics) on my first molar on the left side (lower side). I have never had any problems with teeth or any sensitivity (EVER) before. Now I can not regret enough how I miss my old filling which caused me no discomfort at all. I got it replaced early September with a composite - the filling was too high right after I left so I went back to get it fixed. Still not enough, the next day I went back to smooth it down even more. Then it started to feel more natural but when I was biting into this weird paper to identify my high spots on my tooth I noticed horrible pain. My dentist said it's completely normal because he drilled my tooth a bit so I let it be and went home.

Now, this is when things get tricky - I started noticing this extremely uncomfortable "sensitive" pain from the nerve of that tooth ONLY when I eat food which is crunchy like tortilla chips, nuts, crunchy flakes etc. It always shot this "sensitive pain" from that exact tooth. Now note there were no high points because he checked it and when I bite I felt nothing unusual and no pain.

So around a month ago I decided to go back to my dentist to look on this tooth and he decided to replace composite with amalgam and I got really upset because that defeats the whole purpose -I suffered for nothing to get back into the filling I did not want on the first place. SO he decided to replace my composite with glass ionomer cement. Now I know this filling does not last that long, especially on my molar but I was happy that I might get rid of this pain so I did not care.

As days went by I started eating whatever I wanted and today I ate some crunchy flakes with yogurt and guess what.. it shot this sensitive pain again. When I ate the crust on the pizza I felt it again, and again. I am so desperate. I don't understand why it shoots this pain only when eating crunchy things nor what can be solution or cause of this. He saw nothing wrong with the tooth and said the cavity was not deep AT ALL. He got it replaced the first time and it did not help at all again. I went from fully healthy teeth with no sensitivity to this state of when I'm afraid to eat anything on my left side because of the sensitivity and pain.

Note that I have no sensitivity to cold/hot food, I only feel pain when I chew on that tooth crunchy food.

Thank you for any advice