title: Use of a surgical navigation system for CT-guided template production.
abstract: OBJECTIVE
  The purpose of this study was to evaluate in vitro the accuracy of 2 methods for computerized tomography (CT)-guided template production via a surgical navigation system.
  
  
  METHODS
  Oral implants were planned on CT scans of standard dental stone casts with integrated target pellets. Method 1 used the aiming device of the navigation system for direct positioning of 2-mm surgical bur tubes on the dental stone casts. In method 2, the aiming device was used to guide drillings into the dental stone casts, and the surgical bur tubes were indirectly positioned by metal rods inserted in the drill holes. In both methods the bur tubes were affixed in a resin template. The accuracy of the obtained templates was evaluated by postoperative CT scans using descriptive statistics and the Student t test (P < .05 considered significant).
  
  
  RESULTS
  The mean accuracy (normal deviation from the defined targets) of method 1 was 0.5 +/- 0.3 mm (max 1.2 mm; n = 56). Mean accuracy for method 2 was 0.6 +/- 0.3 mm (max 1.4 mm; n = 56). No significant difference was found between the maxillary and mandibular templates.
  
  
  CONCLUSIONS
  Conventional navigation systems already installed in many hospitals may be used for surgical template production. In contrast to intraoperative tool tracking, there is no need for patient tracking, and the planned implant axis can be rigidly secured as precisely as technically feasible with the help of an aiming device.
  
  
  CONCLUSIONS
  Both methods of bur tube positioning may represent a precise means for CT-guided template production.
authors.affiliation: Interdisciplinary Stereotactic Intervention and Planning Laboratory Innsbruck (SIP-Lab), Innsbruck Medical University, Department of Radiology, Clinical Division of Diagnostic Radiology I, Austria. gerlig.widmann@i-med.ac.at
authors.forename: Gerlig
authors.initials: G
authors.lastname: Widmann
authors.forename: Roland
authors.initials: R
authors.lastname: Widmann
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Widmann
authors.forename: Werner
authors.initials: W
authors.lastname: Jaschke
authors.forename: Reto
authors.initials: R
authors.lastname: Bale
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D003758:Dental Implantation, Endosseous / Q000295:instrumentation*; D015921:Dental Implants; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008334:Mandible / Q000033:anatomy & histology / Q000601:surgery; D008437:Maxilla / Q000033:anatomy & histology / Q000601:surgery; D008768:Methylmethacrylates / Q000737:chemistry; D003765:Models, Dental; D010347:Patient Care Planning; D013238:Stereotaxic Techniques / Q000295:instrumentation; D025321:Surgery, Computer-Assisted; D036542:Tomography, Spiral Computed; D014057:Tomography, X-Ray Computed
chemical_list: D000180:Acrylic Resins; D015921:Dental Implants; D008768:Methylmethacrylates; C091936:Orthocryl