This week, I received a nice present in a jewelry box. It was a crown that came out of a patient’s mouth while she was chewing. Crowns, or “caps”, can sometimes come out or get loose. Patients randomly come in with a crown that ends up in their hand, as it has loosened from the tooth on which it was comfortably resting for years. Luckily, they very rarely are ones that I have made, and usually they are quite old.
I am always fascinated by the way in which patients bring these loose crowns to my office; the usual carrier is a baggie, but I have seen margarine containers and even fancy ring boxes. Either way, we clean and disinfect the loose crown and try it back in the patient’s mouth. We take a digital x-ray and examine the fit with a fine dental instrument. We then check the tooth. If there is no decay and the crown fits well, it is re-cemented. If there is decay that affects the margin and fit of the crown, the decay must be removed and a new crown made. If the decay reaches the nerve, a root canal and a post/core would be needed as well to remove the nerve and disinfect the tooth.
Many times, a crown is placed on a tooth after an endodontic procedure (root canal), and the crown is loose because the post that was placed after the root canal has loosened. The tooth is carefully examined, and if the post has been loose for a while, the root canal may have become re-infected; in this situation, a new root canal, post and possibly a new crown is needed. Usually the post and crown can just be recemented as a simple solution, but careful evaluation is a must to ensure a proper fit and no decay.
Simply, it is imperative to go to a dentist as soon as possible after you notice a crown that may be loose in your mouth. The longer they are loose, the higher the chance that decay may develop and that the crown cannot be reused.
As for implant crowns, they also can loosen. We try to make all implant crowns retrievable, so they can be simply retightened. Another type of implant crown is one that is cemented onto an abutment. If an implant crown is loose that was initially cemented, it is more problematic. The crown may be snug, but the abutment may be loose. In this case, the crown must be taken off the abutment, and then the abutment must be tightened; sometimes, this result in the necessity of making a new crown.
As for our “present” in the jewelry box, we carefully cleaned the crown. We made sure the tooth was healthy and clean without any decay, and our x-ray reveled that the crown still fit well. We used the best and strongest cement and instructed our patient not to chew on her “jewel” for an hour and a half. Our patient was happy with the simple solution.
As always, please let me know if there are other dental topics that you would like me to discuss in this blog!