Root Canal Retreatment: What to Expect

Dentist Articles

Most of the time, a root canal (also called endodontic therapy), in conjunction with a crown, can last a lifetime. Occasionally, however, the root canal treatment fails and it must be retreated. This retreatment is generally done by a root canal specialist, or endodontist. If you find that your endodontically treated tooth needs to be treated again, here is what you can expect from the procedure.

Removal of Old Filling Material

If you've had a root canal done within the past decade or two, your canals were most likely filled with a rubbery material called gutta percha. After your endodontist drills an access hole in the biting surface of your tooth, he or she will place a solvent in your tooth to begin loosening up the gutta percha. A series of small drills and files will be used to remove the old material from your canals so they can be thoroughly cleaned.

If your root canal is older, you might have thin strips of metal called silver points in your canals. These are no longer used, because they tend to corrode over time, but they were a popular root canal filling material in years and decades past. If you have silver points in place and you need to have your endodontic treatment redone, an ultrasonic machine will often be used to loosen them enough to allow them to slide out. Care will be taken to avoid breaking them, but in some cases the silver is corroded enough that they break off inside of the canal. This may or may not lead to the necessity of an additional procedure later.

Widening and Shaping of the Canals

Once the old material is removed, the endodontist will widen and shape your canals more than they were in the original procedure. Sometimes, a root canal retreatment is done because there is an additional canal that was not found during the first treatment. Your specialist will use a surgical microscope to search for additional canals if this is suspected to be the issue. Most of the time, these hidden canals are found in molars, but occasionally there will be an extra canal in a bicuspid tooth.

The endodontist will use tiny files and reamers to widen the canals, just like your dentist did during the first root canal treatment.

Refilling the Canals

In some cases, a temporary antiseptic canal filling will be placed for up to several weeks before the permanent canal filling can be placed. This might be necessary if you have a draining abscess or infection, and it will allow your infection to heal. (If your endodontist gives you a prescription for antibiotics, be sure to take all of them as directed to allow the healing to take place.)

Once there is no more draining infection, your endodontist will refill the canals with new gutta percha filling material. Tiny flexible cones of the gutta percha will be slid into your canals, then heated so they melt and fill every bit of space. Liquid gutta percha is often also injected to continue filling the canals. You might detect a slight burning smell, but you will not feel anything; the nerve in your tooth is gone and the heat will not affect your gums or the other teeth in the vicinity.

When your retreatment is complete, you'll be referred back to your general dentist to have your final restoration done. Often, this will just require filling the hole that was drilled in the crown. Occasionally a new crown might be needed. Be sure to get this taken care of promptly to avoid cracking or fracturing either the crown or the natural tooth.

To learn more about root canal retreatment procedures by speaking with an endodontist, go to sites like this one.

11 January 2016