My Tooth Crown Fell Off Four Times

Posted by AllSmiles

Although our family has had the same dentist for over 15 years, I have given up on my dentist because my crown won’t stay on. I first received a crown for my lower left second molar after a root canal in 2009. My dentist replaced the crown in March 2022. Over the past year, the crown has come off four times. The fourth time it came off was two weeks ago, and I decided not to return to my dentist. I knew I couldn’t leave my tooth bare, so I found an emergency dentist who re-cemented it. She wants me to return to her so she can determine why the crown repeatedly falls off. I’m not sure what to ask or what to do. This ordeal is making me nervous. I wish it would go away, but I know better. I would like to know why the crown keeps coming off. – Thanks. Dakota from NJ

Dakota,

Dr. Michalski would need to examine your crown and tooth to determine why the crown keeps falling off.

Why Does a Dental Crown Fall Off?

If a crown repeatedly falls off, the issue is likely with how your dentist prepared your natural tooth for the crown—not the strength of the cement or bonding. If that is the case, you need a new crown.

When a tooth has a root canal and little structure remains to support a crown, a dentist needs a specific technique to ensure the crown is secure. Although a dentist who understands how to resolve the issue might have a slightly different approach, the process generally includes the following:

• Place and cement a semi-flexible fiberglass post deep into the canal, about 2/3 the length of the tooth
• Bond core material to the tooth and the fiberglass post
• Bond the post into the canal with composite.

The composite builds the core for the crown preparation. This method works because some tooth structure remains. But if a tooth breaks off at the gumline, a post alone will not work. Twisting stresses on the post from daily oral function will dislodge the post, and the crown will keep falling off.

If the dentist with whom you had an emergency visit has advanced cosmetic dentistry training, you may check her patient reviews to decide if you want her to complete the work. Otherwise, look for a dentist with advanced cosmetic training. Talk to the dentist about your increasing anxiety and get details on sedation options to calm you during treatment.

Dr. Thaddeus Michalski, a Rocky Hill, Connecticut dentist, sponsors this post.