title: Accuracy of implant placement using a CAD/CAM surgical guide: an in vitro study.
abstract: OBJECTIVE
  To determine and compare the accuracy of an advanced surgical template based on computer-aided design/computer-assisted manufacture (CAD/CAM) with the conventional surgical template in different respects such as entry point, length, and osteotomy angle.
  
  
  METHODS
  Computed tomography (CT) scanning of a dentate epoxy mandible was performed and its three-dimensional computerized model was simulated. Sixteen rapid-prototyped models were fabricated and divided into two groups. In the first group, a radiographic template was fabricated and placed on the model during CT scanning and then was modified to the conventional surgical template form. In the second group, a coordinate measuring machine was used to reformat a nonanatomic radiographic template fabricated by a stereolithographic machine, and four implants were planned and then placed in the jaw. The differences between planned and actual mesiodistal and buccolingual entry points, lengths, and angles of the implants were measured. Statistical analysis was performed with the Mann-Whitney and Friedman tests to detect differences between groups.
  
  
  RESULTS
  The average differences between the planned and actual entry points in the mesiodistal and buccolingual directions, lengths, and angles of the implants and the osteotomy showed a considerable reduction in the CAD/CAM group versus the conventional group (P < .005).
  
  
  CONCLUSIONS
  The accuracy of implant placement was improved using an innovative CAD/CAM surgical template.
authors.affiliation: Department of Prosthodontics, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Saeid
authors.initials: S
authors.lastname: Nokar
authors.forename: Elnaz
authors.initials: E
authors.lastname: Moslehifard
authors.forename: Tootiaii
authors.initials: T
authors.lastname: Bahman
authors.forename: Masoud
authors.initials: M
authors.lastname: Bayanzadeh
authors.forename: Farzad
authors.initials: F
authors.lastname: Nasirpouri
authors.forename: Arash
authors.initials: A
authors.lastname: Nokar
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D003724:Dental Arch / Q000033:anatomy & histology; D003758:Dental Implantation, Endosseous / Q000295:instrumentation* / Q000379:methods; D015921:Dental Implants; D017267:Dental Prosthesis Design / Q000295:instrumentation*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008334:Mandible / Q000033:anatomy & histology; D003765:Models, Dental; D010347:Patient Care Planning; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted / Q000295:instrumentation / Q000379:methods*
chemical_list: D015921:Dental Implants