IntroductionContinuous improvements in techniques, instruments, and materials have established modern endodontic microsurgery as a state-of-the-art treatment method. The purpose of this approach was to introduce a new surgical endodontic technique by using a three-dimensional printed template for guided osteotomy and root resection. MethodsA 38-year-old patient was diagnosed with periapical lesions of teeth #3 and #4 and extruded gutta-percha material. Three-dimensional radiographic and optical scan files were imported into surgical planning software designed for guided implant surgery. Within the adapted software program the periapical lesions and the extruded gutta-percha were visualized and marked. With the aid of virtually positioned surgical pins and piezoelectric instruments, the osteotomy size, the apical resection level, and the bevel angle were defined before treatment. Three-dimensional surgical templates for each tooth were designed within the software program for a guided treatment approach. ResultsThis approach comprised the treatment of periapical lesions of teeth #3 and #4 with root-end fillings and the detection and complete removal of the extruded gutta-percha material without perforation of sinus membrane. There were no postoperative complications, and clinical and radiologic assessments verified complete healing of the teeth. ConclusionsThe guided microsurgical endodontic treatment presented appears to be a viable technique that allows for predefined osteotomies and root resections.