My back teeth hurt from eating sweet or crunchy stuff. what might be the problem?

I went to the dentist 3 month ago and fixed all my teeth, so i don't have anything on the outside, but it still hurts. I also grind my teeth a lot, may be that influences it. What should I do?
Answer:
it could be that your enamel has worn down and that has caused sensitivity. try Pronamel toothpaste and see if it helps. there are mouthpieces you can wear at night to stop the grinding when you're asleep.

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I would say go back to the dentist cause it sounds like a cavity.

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