I got three upper crowns in early 2020. One of the three crowns has a cavity beneath it. The tooth has been hurting, but I was very surprised when my dentist told me that I had a cavity beneath the crown. I thought the crown was going to protect my teeth from future decay. How could this happen? Will I need a root canal? Will insurance pay for this if I need a new crown, although it is relatively new? – Tristen from Macon, GA
It is unusual to have a cavity beneath a crown after almost four years. A dentist would need to examine your crown and tooth to determine why you have a cavity. But we can provide some basic information about a cavity beneath a crown.
How Can You Have a Cavity Beneath a Crown?
Having a cavity beneath a crown is unusual, but it can occur. What are some possible causes?
- Tooth infection not removed – If a dentist covers a tooth with a crown without removing decay thoroughly, you might develop a cavity.
- Gap at the margin – Your dentist must ensure the margin where your tooth and crown meet is closed and smooth. Even a small gap allows bacteria to creep in. Plaque can build up and promote decay.
If you feel pain or discomfort in the tooth, without treatment, you may need a root canal treatment to remove an infection. Without a root canal, the infection will progress, causing tooth loss and more costly treatment for tooth replacement, such as a dental implant.
Check with your insurance company regarding coverage toward replacing the crown. Many insurance plans expect the crown to last at least five years. If replacement is needed sooner than that, the insurance company will ask for documentation from your dentist to determine if they will provide benefits.
Dr. David Pumphrey, an Atlanta periodontist, sponsors this post.