title: Accuracy of virtually planned and template guided implant surgery on edentate patients.
abstract: OBJECTIVE
  Scientific evidence regarding the accuracy of implants placed into patients by the aid of a surgical template is limited. The objective of the present study was to verify if any variation exists between virtually planned implants' position using a computer, compared with the subsequently clinically placed implants with the aid of a surgical template in the mandible and the maxilla.
  
  
  METHODS
  A total number of 25 edentate jaws were treated with the aid of a surgical template. In total, 139 implants were inserted. Fifty implants were inserted in the mandible and 89 in the maxilla. A voxel-based registration method was used to match two separate cone-beam computed tomography scans of the patients. The implant positions were calculated and compared between the planned implants and the implants' clinical position after more than 1 year after surgery. The results included the linear differences in distance at the level of the hex, the apex, and the depth. The angular differences were presented in degrees.
  
  
  RESULTS
  Statistical results indicated some factors with significant deviations. The greatest errors were found when comparing between patients moving during the computed tomography scans and those that did not move. The results showed significant divergence at the level of the hex and apex of the implants.
  
  
  CONCLUSIONS
  The hypothesis was rejected, as the statistical results indicated that there were significant differences between virtually planned implants' position and the final position of implants placed clinically.
authors.affiliation: Department of Dental Medicine, Division of Image and Functional Odontology, Karolinska Institutet, Huddinge, Sweden. andreas.pettersson@ki.se
authors.forename: Andreas
authors.initials: A
authors.lastname: Pettersson
authors.forename: Ai
authors.initials: A
authors.lastname: Komiyama
authors.forename: Margareta
authors.initials: M
authors.lastname: Hultin
authors.forename: Karin
authors.initials: K
authors.lastname: Näsström
authors.forename: Björn
authors.initials: B
authors.lastname: Klinge
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017076:Computer-Aided Design; D054893:Cone-Beam Computed Tomography / Q000295:instrumentation / Q000706:statistics & numerical data; D003758:Dental Implantation, Endosseous / Q000295:instrumentation* / Q000706:statistics & numerical data; D003766:Dental Occlusion; D004867:Equipment Design; D005260:Female; D057918:Fiducial Markers; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data; D021621:Imaging, Three-Dimensional / Q000706:statistics & numerical data; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery; D008875:Middle Aged; D010347:Patient Care Planning / Q000706:statistics & numerical data*; D025321:Surgery, Computer-Assisted / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014584:User-Computer Interface