title: Accuracy of a computerized tomography-guided template-assisted implant placement system: an in vitro study.
abstract: OBJECTIVE
  To evaluate the accuracy of computer-assisted 3D planning and implant insertion using computerized tomography (CT).
  
  
  METHODS
  Nine implants were planned on pre-operative CTs of six resin models, which were acquired with radiographic templates, using a planning software (E implants). Each resin model contained three pre-existing control implants (C implants). Radiographic templates were converted into operative guides containing 4.8-mm-diameter titanium sleeves. A single set of insertable sleeves was used for consecutively drilling the six models, followed by implant insertion through the guide sleeves. Models were further divided into group A (the first three models) and group B (the last three models). Post-operative CTs were used to compare implant positions with pre-operative planned positions. Statistical analysis included the Mann-Whitney U test for E and C implants and the Wilcoxon's signed ranks test for groups A and B.
  
  
  RESULTS
  The mean apex depth deviations for E and C implants [0.49 mm+/-0.36 standard deviation (SD) and 0.32 mm+/-0.21 SD, respectively], and the mean apex radial deviations (0.63 mm+/-0.38 SD and 0.49 mm+/-0.17 SD, respectively) were similar (P>0.05). The mean angulation deviations for E and C implants were 2.17+/-1.06 degrees SD and 1.33+/-0.69 degrees SD, P<0.05. E implant deviations of all the parameters in group A were significantly smaller than E implant deviations in group B.
  
  
  CONCLUSIONS
  Computer-assisted implant planning and insertion provides good accuracy. Deviations are mainly related to system and reproducibility errors. Multiple use of drills and titanium sleeves significantly reduces system accuracy.
authors.affiliation: School of Graduate Dentistry, Department of Periodontology, Rambam Health Care Campus, Haifa, Israel. jhorwitz@comm.net.il
authors.forename: Jacob
authors.initials: J
authors.lastname: Horwitz
authors.forename: Otman
authors.initials: O
authors.lastname: Zuabi
authors.forename: Eli E
authors.initials: EE
authors.lastname: Machtei
mesh_terms: D017076:Computer-Aided Design; D003758:Dental Implantation, Endosseous / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D021621:Imaging, Three-Dimensional; D003765:Models, Dental; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed