Complications may occur during and after endodontic treatment, which may be due to negligence of the operator. The surgical treatment of a case presenting pain and persistent pus discharge and swelling due to the extrusion of the root canal filling to the base of the nasal floor between left maxillary lateral and canine teeth is presented in this report. First, carelessness was during root canal treatment that was over obturated and second time during extraction in which overextended gutta-percha remained in the bone, caused the complications like pain, persistent pus discharge, and headache. Clinicians should be aware of the fact that endodontic instruments and filling materials (solid or liquid) can be extended in such a degree that can lead to neurological or sinus complications.