You are not crushing ice cubes with your ceramic teeth... are you?
What kind of cement is your dentist using: mortar mix?
I guess that dentists do what they call a "build up" where they glue more bone to the tooth in order to make it fit for receive a crown.
Also, the dentist must do a complete alignment of your teeth immediately or after a few weeks, because less of a millimeter of additional top surface in the new crown might cause a complete misalignment of the entire denture in your mouth. Perhaps this is the reason why you were breaking the new ceramic crowns very often.