The Success of Root Canal Treatment

By Brian J. Gray, DDS, MAGD, FICOI

Many international scientific studies demonstrate that root canal treatment is generally successful and provides an excellent long-term prognosis when properly performed utilizing sound biological and mechanical concepts. As with any clinical situation, there are factors that must be considered when discussing root canal treatment outcomes:

1. Root canal treatment has not always been as successful as it is today. Fortunately, the guiding principles of modern endodontics can now be utilized to deliver very predictable results over years of a patient's lifetime. Some of these principles were unknown or misunderstood in the past and, consequently, many teeth have had endodontic treatment based on concepts, techniques, and materials that are not considered optimal by today's standards. Even so, some of these teeth have given and will continue to provide additional years of good service. In other instances, previously treated teeth exhibit bacterial leakage that may or may not be accompanied by clinical symptoms. Failing endodontically treated teeth can generally be successfully retreated using modern biological concepts, technologies, and techniques.
2. Root canal treatment can be successful even if a tooth is severely damaged by decay, trauma, or other destructive events. In cases such as this, it may be necessary to reinforce the tooth by placing a post into the root before a crown can be placed. In these situations, the dentist must weigh risks versus benefits during the treatment planning process.
3. The success of root canal treatment is greatly enhanced when the tooth receives a protective restoration after completion of the root canal treatment. When a protective crown is not placed, the root canal filling may leak or the tooth may develop additional decay or even fracture. Once a root fracture has occurred, there are generally no predictable treatments to save the tooth.
4. For root canal treatment to be successful, the periodontal supporting structures of the tooth must be healthy or capable of being returned to a state of health with periodontal treatment. Other specialty consultations may also be necessary depending on the findings in a particular situation.
5. To insure that root canal treatment is working, the particular tooth should be evaluated over time. Teeth are subject to enormous shifts in temperature (such as hot coffee vs. ice cream), tremendous mechanical loads (in pounds per square inch), and constant exposure to the bacteria in saliva. Periodic re-evaluation allows the dentist to examine the results of past treatments and to intervene early if new damage or breakdown is occurring.

As with any human endeavor, there are certain clinical situations in which root canal treatment does not work even with the best efforts that modern dentistry can offer. Fortunately, these cases are infrequent and, if they occur, many of the teeth can be successfully retreated by an endodontic specialist. Root canal treatment, when appropriately planned and well-performed, is the most cost-effective and predictable treatment alternative in most clinical situations.