“How do you tell if a tooth crown is not fitted properly?”

The first thing is how does it feel. When you bite and the pressure between the teeth. It is difficult for consumers to tell how the fit is after that. As a dentist I'm looking for a fit of 15 to 40 microns at the spot where the tooth meets the crown. If you can feel a gap with your fingernail or tongue it probably needs checked.

By looking at the X-ray. There should be no gaps at the margin.

It may be difficult to know for sure without an X-ray and exam with an explorer, but if you see any gaps between the root and the crown, can feel your floss hit a ledge or go under the crown. If you’re constantly pulling a lot of food out around it or your floss has no resistance when flossing around it. Also, if you hit it with your other teeth first before the others, it is not balanced or may not be seated correctly.

That would not be possible for a patient to tell if the crown has a slight "fitting" problem. In our office, there are several tests the crown must pass to be acceptable: 1. It must look good, as close to its neighbor teeth appearance as possible (not "stand out") 2. It must fit the tooth around the edges, with no gaps 3. It must touch the adjacent teeth tight enough to keep food from catching, but light enough so dental floss won't break when you pass it through the place where the crown touches neighbor teeth. When using thin unwaxed floss, you put it through the area where the teeth touch the crown, and it should catch slightly. If the floss doesn't catch, food will trap. If the floss breaks, then it's difficult to clean4. It must fit the opposing teeth that fit against it when biting, chewing, or just closing. It must not feel "high" or like when you close, the new crown does not touch the opposing tooth 1st, before other teeth. If it passes those 4 tests, you are probably good to go.

You can tell if the crown is not fitting well: If the bite is off, if the contact between adjacent teeth is off, or if there is a catch at the base of the crown and tooth while you floss.

Dr. Meshkian

Initially if the bite is off, food impaction, and any open areas you might see or get food in at the margin.