Accuracy of a non-contact 3D measuring system for dental model analysis

Purpose: This study aimed to assess the accuracy of digital dental models obtained using a new non-contact 3D measuring system compared to direct measurements made on plaster models as the gold standard. Methods: Three examiners independently examined the sizes of various teeth and the intercanine and intermolar arch width on plaster casts and digital models. Each parameter was measured 10 times on each model under uniform conditions. The order of measurements was changed each time. Results: The means of the 10 parameters were different between the 2 methods, and the absolute differences ranged between 0.07 and 0.23 mm; some of which were statistically significant (P < 0.05). However, all these differences were less than 0.3 mm, so are not considered clinically significant. The ratios of standard deviation and coefficient of variation were larger than 1 in 7 of 10 parameters, suggesting that the reproducibility of the 3D scanner was slightly less reproducible than the direct measurements, but still clinically acceptable. Conclusion: Our non-contact 3D measuring system showed high reliability on repeated measurement of study models, suggesting that the accuracy of model analysis by 3D scanner is equivalent to that of direct measurement of plaster models by digital caliper. Copyright (C) 2013 The Japanese Society of Pediatric Dentistry. Published by Elsevier Ltd. All rights reserved.