4 porcelain crowns broken???

[tadkim]

4 out of my 6 porcelain crowns have either broke completely in two or have chipped with in the past 6 months! They are my top front teeth. They have been breaking one at a time! I have had them for 8 years, they were all put in at the same time. I don't do anything crazy at all with them, I just eat food, and I am very careful at that!Could there be something wrong with the porcelain? Is this normal? My dentist doesn't say anything...I can't afford this! I am scared that my teeth will break at any given moment and that I will be left standing there looking like a jack-o-lantern!

[Jerome Tsang, DDS]

Are you clenching or grinding at night?  Abnormal habits at night can cause a tremendous amount of damage to fillings and crowns in a very short amount of time.

[Jerome Tsang, DDS]

What did your dentist propose in regards to treatment? I understand that you're very careful with them. Unfortunately dental crowns don't last forever and it may be possible they are being worn out or have microcracks in them from years of use and are starting to break down.  Besides the clenching, you don't have any other unusual habits such as pencil biting, etc?  How does your bite feel?  Are the teeth shifting somewhat and causing your bite forces to be different and putting more stress on your crowns?  

[tadkim]

Thank you for listening to my question. I do know that clenching and grinding can cause big trouble. I wear a custom made mouth guard EVERY night! I try to monitor myself during the day and watch for clenching or any other unusual habits. I can't figure out what is wrong or what I am doing wrong. Do you have any other suggestions?