2015 Volume 53 Issue 4 Pages 462-470
Dental cast analysis is indispensable for both dental research and medical practice. The Pediatric Dentistry Department of the School of Dental Medicine at Tsurumi University is planning to employ an R 700 3D Scanner for Orthodontics (3 Shape, Inc. Poland) for three-dimensional scanning as a part of dental cast analysis. However, to the best of our knowledge, the accuracy of data objectively obtained with the scanner and its accuracy for measurements in virtual space have not been reported. For this study, we determined the inherent accuracy of the device, accuracy of the indicator points,and clinical accuracy for measurements of actual dental casts using gauge blocks, dental casts designed for measuring accuracy, and actual dental casts. The following findings were obtained.
1.The accuracy of data obtained in all axial directions with the scanner was within 0.02 mm, thus satisfying the nominal accuracy requirement.
2.The differences for the three-dimensional coordinates of the dental cusp of a canine milk tooth on the right upper jaw between a standard dental cast and its shadow cast were within 0.02 mm in all axial directions, with the deviation significantly smaller for the shadow cast.
3.The results of measurements at eight points in accordance with measurement standards reported by Otsubo et al. showed maximum error and mean error values of 0.52 and 0.22 mm, respectively.
Our results indicate that the accuracy of data obtained using this scanner is satisfactory. It was also demonstrated that the scanner has a measurement accuracy for dental casts of ～0.2 mm in clinical settings. In addition, consistent and highly precise results were easily obtained for measurements of dental casts in virtual space using the scanner.
