What are the risks and complications? More than 95 percent of root canal treatments are successful. However, sometimes a procedure needs to be redone due to diseased canal offshoots that went unnoticed or the fracture of a filing instrument, both of which rarely occur. Occasionally, a root canal therapy will fail altogether, marked by a return of pain. What happens after treatment? Natural tissue inflammation may cause discomfort for a few days, which can be controlled by an over-the-counter analgesic. A follow-up exam can monitor tissue healing. From this point on, brush and floss regularly, avoid chewing hard foods with the treated tooth, and it is also very important to see your dentist in Mexico on a regular basis.