If a root canal treated tooth has a new or persistent infection and it does not seem that retreatment will address the problem, then apical surgery may be required. Fortunately, apical surgery is required less than 5-10% of the time after a root canal but in general, the larger the infection was to start, or the longer it had been present, the higher the chance of the infection not healing. Apical surgery involves making an incision in the gum line and accessing the infected area directly through the side of the bone. The infected tissue and a small portion of the tip of the root are removed to allow a filling (special calcium cement material) to be placed into the root tip and seal the root. Sutures are placed and typically removed after 5-7 days.