Since 2 years ago my teeth started to become fragile and crack easily. I need filling almost once every 2 - 3 months on various teeth. My dentist says it has to do with my grinding, but I am already wearing my night guard, sometimes even during day time.

Can it be due to my poor nutrition? My dentist says that once the teeth are grown nutrition has nothing to do with that anymore, and I never had any problem growing up. Thanks in advance.

I was having that problem too, where over like 1 year period of time where various teeth were cracking and I was getting crowns put on them, I asked what could be causing this and the answer they gave me were that some people are just more pron to this sort of thing then others, and usually it runs in familys to, where the teeth just aren't as strong as some people.

Hope your teeth aren't still cracking...mine finally stopped. :D