When you need a root canal procedure

Here are the instructions we gave to patients when they needed a root canal procedure—what to expect, and what to do after the appointment:

You shows signs of having a tooth infection, or a tooth abscess, which requires root canal treatment, otherwise known as endodontic therapy, in order to save it and to prevent or cure a toothache. While you may have a toothache before this procedure, these treatments have an excellent record of success and durability. Once this treatment is successful, it will never wear out or need any maintenance. It may well last you the rest of your life.

Although dentists may have a greater than a 90% success rate with this treatment, we cannot guarantee success. There is a less than 10% chance that your tooth could require root canal surgery (a procedure done to the tip of the root) after the treatment. There is a less than 5% chance that the tooth would need to be extracted after treatment, either because of a failure of the treatment or cracking of the root. Although an infected tooth can always be extracted, extraction of a back tooth can cause a major disruption of your bite and can weaken adjacent teeth unless the extracted tooth is replaced soon with a bridge or a removable partial. The extraction of a front tooth is unsightly. Extraction of a second molar, if it's the tooth furthest back in your mouth, causes the least disruption of your bite.

In times past, endodontic treatment was usually painful either during treatment or afterward. With what we now know, however, it can usually be done with only minor post-treatment discomfort. Sometimes, however, the ligament that attaches the tooth to your jaw becomes so irritated during and after treatment that the tooth flares up and becomes painful. If that happens, call your dentist as soon as possible. For any pain following root canal treatment, ibuprofen is an excellent medication, as it counteracts the inflammation that causes the pain. It's available from drug stores as generic ibuprofen, or as Nuprin or Advil. Take three of these 200 milligram tablets every six hours if needed.

A tooth that requires an endodontic procedure often has a large filling and/or extensive tooth decay, and is therefore weak. Additionally, after root canal treatment, a tooth will gradually become more brittle and more susceptible to fracture. We recommend restoring it with a core material to strengthen it somewhat soon after the completion of endodontic treatment. Sometimes this can be done during the same appointment. After that, within one to three months, it usually needs to have a dental crown placed. Sometimes, if it is strong enough, a filling may be used to restore it instead of a crown. The fee for the endodontic treatment does not usually include the placing of a core, crown, or filling.

There is a remote risk that root canal procedure could result in irritation or harm to the nerve tissue or other tissues, if they run near the apex of the tooth. This could result in numbness of the lip or a portion of the jaw. Other unforeseen problems or damage could occur.