Caries or trauma may result in infection of the roots of the teeth. The infection can pass from the root of the tooth to the jawbone, causing inflammation around the root. It is possible to improve the tooth with canal treatment in the early period. However, there are sometimes cases where root canal treatment fails; the canals of the tooth may be narrow or curved, there may be no response to repeated canal treatments, or infection at the root tip may not be small enough to be cured by canal treatment alone. Endodontic surgery (root tip resection) is performed in patients with failed or inadequate canal treatment. In these patients, instead of pulling the tooth, the root end of the tooth is reached by a surgical operation and the inflammation or cyst at the root end and some part of the tooth root are removed. It can be applied to all teeth including molars. Root canal treatment of the tooth should be performed before this operation. This operation needs to be carried out very meticulously. Because in stubborn cases, the operation may need to be repeated. The patient should be checked regularly after the operation.