Ever look at that new crown put in less than 5 years ago and see that half of it is missing? This is especially true in the back of the mouth (posterior) where the forces that you bite with can sometimes overcome the strength of the materials used. This is often true of the “full ceramic” crowns, and the new “Zirconia” crowns. In a study presented at the recent American Association of Dental Research it was reported that after just 2 years almost 40% of this type of crown failed usually splitting in half and necessitating complete replacement. It’s generally due to surface cracks that grow (that’s called crack propagation), connect and then the crown fails. The cracks are from the manufacturing of the crown by the lab or when we have to make adjustments before seating the crown in your mouth. In our practice we use a metal re-enforced crown called a PFM (porcelain fused to metal) which helps avoid these cracks and fractures. Any porcelain can crack and fail, but generally PFMs last longer in the back potions of the mouth. We tend to want to use the conservative method, the PFM, in our practice but always want to give options and respect the wishes of our patients.