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Root Canal the Second Time Around

A root canal can fail for several reasons. If the bacteria were not completely removed from the canals, they can multiply and cause pain. Bacteria can also reinfect a tooth if a permanent filling was not placed very soon after the root canal treatment. Temporary fillings or poorly placed permanent fillings can break down or leak. This allows bacteria back into the canal.

Sometimes the dentist does not locate all the canals in a tooth. This can occur if a tooth has more than the typical number of canals for the type of tooth. The bacteria in the unfilled canal will multiply and start to cause pain.

A repeat root canal treatment tends to be more involved and take more time than the first one. Your dentist must remove the crown, post and core, and filling material before doing the second root canal. Some people who need another treatment may have infections that are difficult to control.

Sometimes a second root canal can be hard to do. For example, it may be too risky to remove a post and core. The post that is in the tooth may be cemented or set in very tightly. If that is the case, the tooth may be fractured in the process. So your dentist may decide to do endodontic surgery instead.

This surgery allows the dentist to get inside a tooth's root from the bottom of the tooth, rather than from the top (the crown).

Endodontic surgery is done in the dentist's office. An endodontist, general dentist or oral surgeon can perform this procedure. First, you will receive a shot to numb the area. Then your dentist will make a small cut (incision) in the gum near the base of the tooth. He or she will clean out the infected tissue around the tip (apex) of the root and shave off the tip. This procedure is called an apicoectomy. The endodontist will clean the inside of the canal from the root end, and then put a filling in the end of the root. The incision is then stitched.

Endodontic surgery is successful about 85% of the time. It is typically done only on premolars and front teeth. If the surgery does not get rid of the infection, the tooth will have to be extracted.

Last updated May 13, 2014