title: Evaluation of the accuracy of 7 digital scanners: An in vitro analysis based on 3-dimensional comparisons.
abstract: BACKGROUND
  As digital impressions become more common and more digital impression systems are released onto the market, it is essential to systematically and objectively evaluate their accuracy.
  
  
  OBJECTIVE
  The purpose of this in vitro study was to evaluate and compare the trueness and precision of 6 intraoral scanners and 1 laboratory scanner in both sextant and complete-arch scenarios. Furthermore, time of scanning was evaluated and correlated with trueness and precision.
  
  
  METHODS
  A custom complete-arch model was fabricated with a refractive index similar to that of tooth structure. Seven digital impression systems were used to scan the custom model for both posterior sextant and complete arch scenarios. Analysis was performed using 3-dimensional metrology software to measure discrepancies between the master model and experimental casts.
  
  
  RESULTS
  Of the intraoral scanners, the Planscan was found to have the best trueness and precision while the 3Shape Trios was found to have the poorest for sextant scanning (P<.001). The order of trueness for complete arch scanning was as follows: 3Shape D800 >iTero >3Shape TRIOS 3 >Carestream 3500 >Planscan >CEREC Omnicam >CEREC Bluecam. The order of precision for complete-arch scanning was as follows: CS3500 >iTero >3Shape D800 >3Shape TRIOS 3 >CEREC Omnicam >Planscan >CEREC Bluecam. For the secondary outcome evaluating the effect time has on trueness and precision, the complete- arch scan time was highly correlated with both trueness (r=0.771) and precision (r=0.771).
  
  
  CONCLUSIONS
  For sextant scanning, the Planscan was found to be the most precise and true scanner. For complete-arch scanning, the 3Shape Trios was found to have the best balance of speed and accuracy.
authors.affiliation: Associate Professor, Department of Oral Rehabilitation and Restorative Dentistry, College of Dental Medicine, Medical University of South Carolina, Charleston, SC. Electronic address: renne@musc.edu.
authors.forename: Walter
authors.initials: W
authors.lastname: Renne
authors.affiliation: Assistant Professor, Department of Oral Rehabilitation and Restorative Dentistry, College of Dental Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Mark
authors.initials: M
authors.lastname: Ludlow
authors.affiliation: Predoctoral student, College of Dental Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: John
authors.initials: J
authors.lastname: Fryml
authors.affiliation: Predoctoral student, College of Dental Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Zach
authors.initials: Z
authors.lastname: Schurch
authors.affiliation: Assistant Professor, Department of Oral Rehabilitation and Restorative Dentistry, College of Dental Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Anthony
authors.initials: A
authors.lastname: Mennito
authors.affiliation: Assistant Professor, Department of Oral Rehabilitation and Restorative Dentistry, College of Dental Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Ray
authors.initials: R
authors.lastname: Kessler
authors.affiliation: Assistant Professor, Division of Biostatistics and Epidemiology, Department of Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Abigail
authors.initials: A
authors.lastname: Lauer
mesh_terms: D017076:Computer-Aided Design; D000068598:Data Accuracy; D003627:Data Interpretation, Statistical; D003724:Dental Arch / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D015921:Dental Implants; D003761:Dental Impression Technique; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation* / Q000379:methods*; D066298:In Vitro Techniques; D003765:Models, Dental; D015203:Reproducibility of Results; D012984:Software; D013997:Time Factors
chemical_list: D015921:Dental Implants