title: Evaluation of the difference in accuracy between implant placement by virtual planning data and surgical guide templates versus the conventional free-hand method - a combined in vivo - in vitro technique using cone-beam CT (Part II).
abstract: OBJECTIVE
  The purpose of this study was to assess the accuracy of implant placement after virtual planning of implant positions using cone-beam CT data and surgical guide templates, and to match the results with those achieved with the conventional free-hand method.
  
  
  METHODS
  Twenty-three implants were placed in 10 patients with a Kennedy Class II with 3-dimensional (3-D) planned surgical guide template. Manual implantation was performed in anatomical casts of the same patients by a prosthodontist and a maxillofacial surgeon. Postoperative images of casts were superimposed onto the preoperative image of virtual planned ideal position of the implant.
  
  
  RESULTS
  The 3-D surgical guide template produced significantly smaller variation between the planned and actual implant positions at the implant shoulder (0.9 mm (0-4.5)) and apex (0.6-0.9 mm (0.0-3.4)) compared with the free-hand implantation (2.4-3.5 mm (0.0-7.0); p=0.000 and 2.0-2.5 mm (0.0-7.7); p=0.002). Accuracy of axis was also significantly improved.
  
  
  CONCLUSIONS
  Accuracy of implant placement after virtual planning of implant position using cone-beam CT data and surgical templates is high and significantly more accurate than free-hand insertion. The demonstrated method of superimposing radiographic images of postoperative casts and virtual planning images is a useful method, which allows reduced patient radiation exposure.
authors: Department of Prosthodontics, University Hospital Erlangen, Glückstr. 11, G-91054 Erlangen, Germany. dr.a.nickenig@t-online.de
authors: Hans-Joachim
authors: HJ
authors: Nickenig
authors: Manfred
authors: M
authors: Wichmann
authors: Jörg
authors: J
authors: Hamel
authors: Karl Andreas
authors: KA
authors: Schlegel
authors: Stephan
authors: S
authors: Eitner
mesh_terms: D000328:Adult; D054893:Cone-Beam Computed Tomography; D003758:Dental Implantation, Endosseous / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007568:Jaw / Q000000981:diagnostic imaging*; D008875:Middle Aged; D008953:Models, Anatomic; D010347:Patient Care Planning; D025321:Surgery, Computer-Assisted; D014584:User-Computer Interface; D055815:Young Adult