title: Evaluation of three different validation procedures regarding the accuracy of template-guided implant placement: an in vitro study.
abstract: OBJECTIVE
  The study aims to evaluate the accuracy of the NobelGuide™ (Medicim/Nobel Biocare, Göteborg, Sweden) concept maximally reducing the influence of clinical and surgical parameters. Moreover, the study was to compare and validate two validation procedures versus a reference method.
  
  
  METHODS
  Overall, 60 implants were placed in 10 artificial edentulous mandibles according to the NobelGuide™ protocol. For merging the pre- and postoperative DICOM data sets, three different fusion methods (Triple Scan Technique, NobelGuide™ Validation software, and AMIRA® software [VSG - Visualization Sciences Group, Burlington, MA, USA] as reference) were applied. Discrepancies between the virtual and the actual implant positions were measured.
  
  
  RESULTS
  The mean deviations measured with AMIRA® were 0.49 mm (implant shoulder), 0.69 mm (implant apex), and 1.98°mm (implant axis). The Triple Scan Technique as well as the NobelGuide™ Validation software revealed similar deviations compared with the reference method. A significant correlation between angular and apical deviations was seen (r = 0.53; p < .001). A greater implant diameter was associated with greater deviations (p = .03).
  
  
  CONCLUSIONS
  The Triple Scan Technique as a system-independent validation procedure as well as the NobelGuide™ Validation software are in accordance with the AMIRA® software. The NobelGuide™ system showed similar or less spatial and angular deviations compared with others.
authors.affiliation: Department of Oral Surgery, Bernhard Gottlieb University School of Dentistry, Medical University of Vienna, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Vasak
authors.forename: Georg D
authors.initials: GD
authors.lastname: Strbac
authors.forename: Christian D
authors.initials: CD
authors.lastname: Huber
authors.forename: Stefan
authors.initials: S
authors.lastname: Lettner
authors.forename: André
authors.initials: A
authors.lastname: Gahleitner
authors.forename: Werner
authors.initials: W
authors.lastname: Zechner
mesh_terms: D017076:Computer-Aided Design; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D066298:In Vitro Techniques; D007575:Jaw, Edentulous / Q000534:rehabilitation; D008334:Mandible; D011140:Polyurethanes; D012984:Software; D025321:Surgery, Computer-Assisted; D016896:Treatment Outcome
chemical_list: D015921:Dental Implants; D011140:Polyurethanes
keywords: computer-assisted; computerized tomography; flapless implant surgery; precision; stereo lithography; surgical guides