Root Canal Retreatment

By Brian J. Gray, DDS, MAGD, FICOI

Can an Endodontically Failing Tooth Be Retreated?

Even when pain and/or swelling is present, the majority of failing endodontically-treated teeth can be successfully retreated in today's world of clinical possibility. By using scientific information gathered from research and clinical studies, clinicians have developed better endodontic concepts, materials, and techniques. Additionally, there are now better-trained general dentists and specialists alike. All of these factors translate into improved care for patients. The significant technological breakthroughs that benefit both doctors and patients in endodontic retreatment include:

1. Magnification glasses, fiber optic lighting sources, headlamps, and recently, the dental operating microscope have significantly improved vision and hence elevated treatment success.
2. Ultrasonic devices allow doctors to more efficiently and completely remove old root canal filling materials and other intracanal obstructions so that teeth may be successfully retreated.
3. Computer digital radiography technology allows the doctor to better diagnose, visualize, and treat root canal disease. Additionally, this technology significantly reduces radiation exposure to the patient.
4. Improved instruments, better materials for filling and repairing canals, and innovative new technologies have all contributed to significantly improved retreatment success.

Today, well-trained general dentists and specialists alike can oftentimes perform non-surgical endodontic retreatment in a very predictable, cost-effective, and time saving manner when compared to other treatment alternatives. At times, however, retreatment cannot be managed with non-surgical efforts alone. In these situations, and as an alternative to extraction, a surgical approach may be necessary.

What Is Non-Surgical Root Canal Treatment (NSRCT)?

Non-surgical root canal treatment is a procedure directed towards saving an endodontically failing tooth. At times, the patient's existing artificial crown must be removed. In other instances, access through the crown may be possible. The access opening is created in order to give the dentist non-surgical access into the root canal space through the biting surface of the tooth. Once this has been accomplished, a non-surgical retreatment procedure oftentimes requires:

• Locating and treating previously missed canals.
• Removing old filling materials from the root canal space.
• Removing posts and broken instruments.
• Enhancing existing root canal treatment.
• Negotiating blocked canals and bypassing canal ledges.
• Repairing mechanical and pathological perforations in the root.

Once these objectives have been accomplished, the root canal system is re-cleaned, re-shaped, disinfected, and three-dimensionally sealed. A protective restoration can then be placed and the tooth restored to a state of health and function.

What Is Surgical Root Canal Treatment (SRCT)?

Surgical root canal treatment is a procedural effort in which it is necessary to elevate a small flap of tissue adjacent to the involved tooth in order to gain access to and treat root canal disease. Surgical root canal treatments are usually minor, in-office procedures performed under local anesthesia. Once the pathological area is exposed, the doctor performs a "curettage" to remove the diseased tissue from around the root. This is usually followed by an "apicoectomy," a procedure in which the diseased portion of the root is removed. A small filling is then usually placed to seal the remaining portion of the root. Surgical root canal treatment will oftentimes result in a good long-term prognosis for the tooth if the cause of pathology can be effectively eliminated.

Unfortunately, on occasion, retreatment efforts may not be possible or cost-effective and extraction may be the only alternative. However, saving a tooth that has been previously treated endodontically and is failing is usually possible, can be very predictable, and is typically the most conservative option for the patient.