It is a common scenario in dentistry for a tooth that already has a crown to develop issues requiring further intervention. A frequent question arises regarding whether a root canal can be performed on such a tooth. The answer is generally yes, a root canal can often be successfully completed through an existing crown. This approach aims to preserve the existing restoration while addressing the underlying dental problem.
Understanding the Need for a Root Canal After a Crown
Even after a tooth has been restored with a crown, its internal pulp tissue remains susceptible to infection or damage. One common reason for a root canal on a crowned tooth is the development of new decay. Bacteria can infiltrate beneath a crown if its seal becomes compromised, leading to cavities that reach the tooth’s innermost pulp chamber. Trauma to the tooth, such as a strong impact, can also cause the pulp to become inflamed or necrotic, necessitating root canal therapy.
Sometimes, a pre-existing infection or inflammation might not have been apparent when the crown was placed. Additionally, deep fillings or extensive dental work performed before the crown was seated could have caused delayed pulp irritation. In other instances, a tooth might experience a crack that extends into the pulp, allowing bacteria to enter and cause infection.
The Procedure Through a Crown
Performing a root canal through an existing crown involves a precise sequence of steps to access and treat the infected pulp. The dentist typically begins by creating a small access opening through the top surface of the crown. This opening is strategically placed to align with the pulp chamber and root canals beneath the crown. Dental drills are used with precision to ensure proper angulation and avoid unnecessary removal of tooth structure.
Once the access is established, specialized instruments are used to remove the infected or damaged pulp tissue from inside the tooth. The internal canals are then cleaned, shaped, and disinfected using irrigating solutions to eliminate bacteria and debris. Following thorough cleaning, the canals are filled with gutta-percha to seal the space. Finally, the access opening in the crown is temporarily sealed, completing the initial phase of the procedure.
Considerations After the Procedure
After a root canal is performed through a crown, there are several important considerations for the tooth’s long-term health and the crown’s integrity. Immediately following the procedure, a temporary filling is placed in the access opening of the crown to protect the treated tooth. It is important to return to the dentist promptly for a permanent restoration to properly seal this access hole. This permanent seal helps prevent recontamination of the root canal system.
While the goal is to preserve the existing crown, its integrity is important for long-term function. Making an access opening in a crown can compromise its lifespan, and the crown may eventually need replacement. If the crown is damaged during the procedure, or if its seal is poor after the root canal, a new crown might be necessary. Patients may experience mild discomfort or sensitivity for a few days following the procedure, which can typically be managed with over-the-counter pain relievers. Avoiding chewing on the treated tooth until the permanent restoration is in place is often advised.
When a Different Approach is Necessary
In some situations, performing a root canal through an existing crown may not be suitable. One such instance is when severe decay has developed extensively under the crown, compromising a significant portion of the underlying tooth structure. In these cases, the tooth might not have enough sound structure remaining to support the crown after the root canal, making crown removal necessary for proper treatment and restoration.
Additionally, if the existing crown is old, ill-fitting, or already compromised with cracks or poor margins, it may need to be removed before the root canal begins. Drilling through certain crown materials, such as some types of porcelain, can also be challenging and carry a higher risk of fracturing the crown. In these scenarios, the crown is carefully removed to allow for direct access to the tooth, the root canal is completed, and a new crown is typically fabricated and placed afterward to restore the tooth.