When A Root Canal Fails

Root canals are put forth as a way to save failing teeth. However:

  • Root canals often fail, which requires the same painful and expensive procedure to be done on the same tooth over and over.
  • Each root canal and post placement further weakens the tooth, meaning eventual extraction is likely.
  • Caps or crowns placed after a root canal only have a life of about 7–10 years, meaning multiple replacements over a lifetime.
  • Dental implants replace the painful tooth completely with a realistic-looking tooth that can last a lifetime.

When a Tooth Needs a Root Canal

A constant nagging toothache, extreme sensitivity to heat or cold, or painful "twinging" often indicates a problem deep within a tooth. Your dentist may discover that one of your teeth is deteriorating from the inside out when he or she takes a dental X-ray. The usual course of action is a root canal, but many patients hesitate, fearing more pain as well as the possibility that the procedure will not solve their problem.

A root canal is a procedure that is performed when the nerve tissue and pulp material inside a tooth become infected with bacteria. Because of the enclosed nature of a tooth, the body has little chance to fight and conquer this infection. The result will often be an extremely painful toothache. Sometimes the nerves and live material of the inner tooth will simply die off, and the bacterial infection will continue undetected, doing damage to the tooth, gum, and bone around it. In most cases, a root canal is the standard method of treatment.

The root canal involves drilling in through the center of the tooth and removing the soft material of the pulp. To eliminate all bacteria, the inside of the tooth is cleaned with circular files and filled with gutta-percha, a biocompatible plant material. The tooth is then capped with a restorative crown.

Are there any alternatives to root canal?

For many years, a root canal was presented as the only treatment for inner tooth pain and decay. Today, however, complete extraction of the infected tooth followed by a dental implant might be the preferred method of treatment.

Why choose an implant over a root canal?

Ideally, each time a root canal is performed, all the bacteria would be removed from your tooth during the root canal process, and the tooth would be filled and capped. In cases in which decay is so severe that there is not enough remaining structure to hold the crown, a post is inserted to provide a secure point at which to adhere the cap to the tooth. Unfortunately, this further weakens the tooth and increases the risk of the tooth completely fracturing, making the entire procedure a loss. An implant is comparable in cost to a root canal and has a much higher likelihood of success.

There are three additional reasons why a permanent dental implant might be a better option than a root canal.

  • If even the smallest amount of bacteria is missed, it will be packed back down into the tooth with the filling and will begin to multiply again. Eventually, another root canal will be required—and each drilling reduces your healthy tooth even more, not to mention the pain of the procedure.
  • Weakened teeth often break during the process of being drilled, so the tooth ends up having to be extracted anyway.
  • The cap or crown commonly used to top the tooth after a root canal only has a life span of 7–10 years, meaning you will have to keep replacing it, which is an added expense. Also, if a cap or crown breaks, bacteria could get into the tooth again before you have a chance to get to a dentist, resulting in another infection. If you choose to reject a root canal in favor of tooth extraction and a dental implant, you know that the bacteria in the tooth is removed completely, meaning no more toothaches. With success rates of 90–97 percent, a dental implant (which is designed to last a lifetime) Is often a good alternative.

When a Root Canal Fails

Sometimes root canal therapy is done but is not successful in controlling the disease around the tooth. Many times this is detected by the presence of a dark area around the tip of a root on an X-ray. Basically, this dark area is the body dissolving the bone around the root tip in response to the bacteria still associated with the root. At times, this can create an extremely painful infection. Sometimes the infection continues to spread for years without any symptoms. Treatment options in the case of a failed root canal include redoing the root canal or an apicoectomy.

Redoing the root canal involves drilling through the crown, removing any posts that have been placed, removing the previous root canal filling, refiling the roots, refilling the roots, and placing a new post and possibly a new crown. Depending on the skill of the person retreating the tooth and the nature of the tooth itself, this treatment may or may not be successful. It is always a disappointment when a patient is told that the thousands of dollars spent on retreating a root canal have not accomplished the objective of resolving the disease around the tooth and that additional treatment is needed. Many patients opt for placing a dental implant rather than retreating a root canal in order to avoid this possibility.

The second option for treating a failed root canal is a procedure called an apicoectomy. In this procedure, the gum is reflected from the bone, a hole is drilled in the bone so that the tip of the root can be cut off, and the infection from the root tip area is removed. A filling is then placed in the tip of the root in an attempt to seal the bacteria inside the tooth and stop it from getting into the bone. The success of this treatment can range from 50–90 percent, depending on the skill of the practitioner and the nature of the tooth. As with retreating the root canal, it is a disappointing moment when a patient is told that the apicoectomy was not successful and extraction and a dental implant are needed. Many patients opt for the dental implant in the first place to same time and money as well as to have the best possible long-term prognosis.

How does a dental implant differ from a root canal and crown?

Instead of trying to cap or crown whatever is left of a previously infected tooth, a dental implant replaces the tooth entirely. Unlike a bridge, which might be the next step when a root canal and crown fail, a dental implant feels and works just like your natural tooth.

The implant process is started by gently and painlessly inserting a titanium root replacement into the jawbone. Once healing has taken place and integration of the screw is complete (generally in 8 weeks), a prosthetic tooth is placed on the screw. It will look and feel like the real thing. You care for an implant in the same manner that you care for the rest of your teeth—standard brushing, flossing, and rinsing.

Most patients comment that the dental implant feels just like a natural tooth, and some even claim that it feels like the strongest tooth in their mouth.