A tooth that had root canal treatment some time ago starts to ache when you bite, or a small pimple keeps reappearing on the gum above it. An X-ray shows a dark patch at the root tip where infection has lingered. Sometimes the best way to deal with that is through the tooth again, and sometimes it is from the other end: a small operation through the gum called an apicoectomy, or root-end surgery, which removes the tip of the root and seals the canal from below.
When surgery is considered instead of another root canal
Root canal treatment heals most infected teeth, but bacteria can survive in a canal that is very narrow, curved, branched or blocked. When infection persists, the usual first step is root canal retreatment, where the tooth is reopened and the canals cleaned again from the top.
Root-end surgery comes into the picture when going back through the tooth is impractical or has already been tried. Typical reasons include a crown and post that would be risky to remove, a canal blocked by a broken instrument or calcification, or infection that has not cleared after a well-done retreatment. It is also used occasionally when a sample of tissue around the root tip is needed for diagnosis.
Modern technique has changed the odds
Root-end surgery used to have a mixed reputation. A meta-analysis comparing older and newer methods found that traditional root-end surgery healed in about 59% of cases, while endodontic microsurgery, using an operating microscope or high magnification, ultrasonic tips to prepare the canal end and modern sealing materials, healed in about 94% (Setzer and colleagues, Journal of Endodontics, 2010). These figures come from published studies, and the outlook for any individual tooth depends on its root, the cause of the infection and the quality of the crown or filling on top.
What happens on the day
The area is numbed with local anaesthetic, so you should feel pressure and movement but not pain. The surgeon makes a small cut in the gum and lifts it back to see the bone over the root. A small window is made in the bone, and the infected tissue around the root tip is removed. The last few millimetres of the root, where hidden branches of the canal often lie, are trimmed off.
Under magnification, a short cavity is prepared in the end of the canal and filled with a sealing material that is well tolerated by the body. The gum is then put back in place and held with fine stitches.
Root-end surgery may be carried out by a dentist with surgical experience, or you may be referred to a registered endodontist or oral surgeon, depending on the tooth and its position.
The first week afterwards
Swelling and some bruising of the gum or cheek are common for the first few days. A cold pack on the outside of the face during the first day, and over-the-counter pain relief taken as directed, usually keep things comfortable. Soft food and chewing on the other side help. Rinse gently as instructed, keep brushing the rest of the mouth, and avoid smoking, which slows healing.
Stitches are removed or dissolve within about a week. The bone under the gum takes longer to fill in, so a follow-up X-ray is usually taken some months later to confirm it is healing.
How it compares with removing the tooth
If surgery is not suitable or does not succeed, the alternative is to remove the tooth and replace the gap with an implant, bridge or denture, or leave the space. Keeping a natural tooth avoids the cost and time of a replacement, but only when the tooth has a sound root, enough healthy structure and a good restoration. Our comparison of implants, bridges and dentures sets out the replacement options, and our article on saving a tooth versus removing it covers the earlier decision.
Questions people ask about root-end surgery
Will the tooth be weaker with a shorter root?
Removing a few millimetres from the tip does not usually make a real difference to a tooth with a healthy, well-supported root. A tooth with a crack, very little bone support or a short root to begin with may not be a good candidate.
Can a cracked tooth be saved this way?
Usually not. If the infection is caused by a crack running down the root, surgery cannot seal it, and removing the tooth is normally the better option.
Will I need time off work?
It varies. Some people return to desk work the next day, while others prefer a day or two off if swelling is noticeable. Heavy exercise is best avoided for a few days.
If a root-treated tooth keeps flaring up, have it assessed before the infection spreads further. You can book a review and see current options on our offers page.
