Abstract

Accuracy of Digital Impressions Achieved from Five Different Digital Impression Systems

Ala Omar Ali

Objective: This study aimed to compare the accuracy of digital impressions obtained from various digital impression systems.

Material and methods: A typodont was prepared for a three-unit bridge, and an epoxy resin model of this preparation was designed as a reference model. A lab scanner was then used to record a digital copy of the reference model. The different systems (3M Lava C.O.S., 3Shape D900, Cadent iTero, CEREC Bluecam, and E4D Dentist) were used to scan the epoxy resin reference model and create five digital impressions each (n=5). Using computer software, the differences in spatial measurements between the digital reference model and digital impressions and were calculated. The accuracy was evaluated based on the mean difference and standard deviation in micrometers (μm) for each system?s set of five digital impressions.

Results: The measurements for mean difference (standard deviation) were as follows: CadentiTero-23 (3) μm, 3M Lava C.O.S. - 36 (19) μm, 3Shape D900- 44 (18) μm, CEREC Bluecam - 68 (12) μm, E4D Dentist - 84 (4) μm. The One Way ANOVA test was significant (p ≤ 0.001).Multiple comparison post-hoc tests showed that the E4D Dentist system was significantly different from the Cadent iTero, 3M Lava C.O.S., and 3ShapeD900systems. Also, CEREC Bluecam exhibited significant differences from Cadent iTeroand3M Lava C.O.S. At the same time, there were no significant differences between Cadent iTero, 3M Lava C.O.S., and 3ShapeD900.

Conclusion: Within the limitations of this study, the following conclusions were drawn: 1) There were statistically significant differences between the accuracyof the digital impression systems. More specifically, this difference was most notable when comparing the systems that achieved lower accuracy measurements versus those that demonstrated accuracy on the high end. 2) Digital impressions from the Cadent iTero system were the most accurate. Clinical significance of the study: The results of this study could affect the decision of the clinician on selecting an appropriate Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) scanner for digital impressions. Furthermore, the results carry implications of whether digital impressions are accurate enough to be used as an alternative to conventional impression techniques.