Many at times we have patients who come and say that they do have a persistent swelling in the area where they have had a root canal done early, may be recently. The swelling may or may not be present when they come to us. What is important in the diagnosis is what is the origin of this swelling what we see. If the origin is of the root canal, any kind of pain or the history that is given by the patient or by percussion where the dentist taps and checks where if there is pain in that area or by radiographs done. Usually if there is a swelling associated with the root canal, we can see right at the tip of the tooth where the swelling is happening or it could be at the side of the root all along the root surface. The main reason for this is a failing root canal that was done recently or long time ago. The swelling usually does not bother, many at times the patients say that it does not hurt us. The reason for that is when the infection happens in the tooth, it starts burrowing the bone from there. As it makes its way through the bone and it has an outlet to drain out. That is pus that is formed there. So once the pus is drained out, the swelling really doesn’t hurt, but what is keeps doing is, it keeps destroyed the surrounding bone and the other teeth that are the healthy teeth are compromised because of this. So it is very important to check the prognosis of this. If it is of the tooth origin, and to address it at the earliest.