title: Guided Endodontics: a novel treatment approach for teeth with pulp canal calcification and apical pathology.
abstract: OBJECTIVE
  To present a new treatment approach for teeth with pulp canal calcification (PCC) which require root canal treatment.
  
  
  METHODS
  A 15-year-old male patient presented with pain of his upper right central incisor. The tooth showed signs of apical periodontitis. Due to PCC, location of the root canal was judged to be difficult and associated with a high risk of perforation. A cone beam computed tomography (CBCT) and an intra-oral surface scan were performed and matched using software for virtual implant planning. After planning the position of the drill for root canal location, a virtual template was designed, and the data were exported as an STL file and sent to a 3D printer for template fabrication. The template was positioned on the anterior maxillary teeth. A specific drill was used to penetrate through the obliterated part of the root canal and obtain minimally invasive access to the apical part. The root canal was accessible at 9 mm distance from the apex. Further root canal preparation was carried out using an endodontic rotary instrumentation system. After an interappointment dressing for 4 weeks, the root canal was filled with vertically condensed gutta-percha using an epoxy sealer. The access cavity was restored with a composite material. After 15 months, the patient was clinically asymptomatic with no pain on percussion. The radiograph showed no apical pathology.
  
  
  CONCLUSIONS
  The presented guided endodontic approach seems to be a safe, clinically feasible method to locate root canals and prevent root perforation in teeth with PCC.
authors.affiliation: Department of Conservative Dentistry and Periodontology, Center of Dental Traumatology, University of Würzburg, Würzburg, Germany.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Krastl
authors.affiliation: Department of Periodontology, Endodontology and Cariology, Center of Dental Traumatology, University of Basel, Basel, Switzerland.
authors.forename: Marc S
authors.initials: MS
authors.lastname: Zehnder
authors.affiliation: Department of Periodontology, Endodontology and Cariology, Center of Dental Traumatology, University of Basel, Basel, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Connert
authors.affiliation: Department of Periodontology, Endodontology and Cariology, Center of Dental Traumatology, University of Basel, Basel, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Weiger
authors.affiliation: Department of Oral Surgery, Oral Radiology and Oral Medicine, Center of Dental Traumatology, University of Basel, Basel, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kühl
keywords: Dental trauma; apical periodontitis; guided endodontics; pulp canal calcification; root canal treatment; template