Porcelain chipping on crowns

One of the frustrating parts of dentistry is when a patient reports that their crown has chipped. For most cases it’s the porcelain that is chipping on a porcelain fused to zirconium or metal crown, or it could be an all porcelain crown. In any case, it’s frustrating to spend the money on a crown only to need a new one a 7 or 8 years down the road.

Crown repair Materials

There are repair materials. A special surface bonding is placed on the porcelain and then composite is placed over the porcelain and polished to make it look like the crown. I haven’t seen too many of these hold up very well on front teeth when added. On back teeth with a stronger bite, I wouldn’t even try it. In the back, if the porcelain chip is small and the patient isn’t packing food, I just smooth it up and leave it. If the patient is packing food, it’s time for a new crown.

So what material to use? All metal with no porcelain is just not pretty, and most patients will not accept this, even if it is the last tooth in the arch.

All zirconium is all metal (zirconium is a metal). It is esthetic and will hold up to significant grinding. But of course, nothing is perfect. If placed on a tooth that is chewing opposite a natural tooth, the natural tooth will wear down (there is more friction coming from the zirconium than the natural tooth). Also, if you have to remove the crown, it is difficult to cut zirconium and requires extra time to cut off.

What I frequently do is to try to make the contact areas (where the porcelain breaks) in metal, whether it is zirconium or a traditional metal alloy for crowns, and make the remainder in porcelain. It is a reasonable solution to minimize the number of crowns that will break in the future and still provide an esthetic crown.

Crowns in the anterior (front teeth) and premolar crowns can be made in a newer, stronger all porcelain material. This has been doing very well for dentists, without much chipping. I would be hesitant to recommend this material in the molar area where the chewing forces are greater.

Materials of the Future

There is always more research into improving dental materials. So, what is in vogue now may be replaced by a better product within a few years. There is always a push toward stronger, more esthetic, more biocompatible materials.