Abstract
This study aimed to investigate the transfer accuracy (trueness and precision) of three different intraoral scanning families using different hardware and software versions over the last decade from 2012 to 2021, compared to a conventional impression. Therefore, an implant master model with a reference cube was digitized and served as a reference dataset. Digital impressions of all three scanning families (True definition, TRIOS, CEREC) were recorded (n = 10 per group), and conventional implant impressions were taken (n = 10). The conventional models were digitized, and all models (conventional and digital) were measured. Therefore, it was possible to obtain the deviations between the master model and the scans or conventional models in terms of absolute three-dimensional (3D) deviations, deviations in rotation, and angulation. The results for deviations between the older and newer scanning systems were analyzed using pairwise comparisons (p < 0.05; SPSS 26). The absolute 3D deviations increased with increasing scan path length, particularly for the older hardware and software versions (old vs. new (MW ± SD) True Definition: 355 ± 62 µm vs. 483 ± 110 µm; TRIOS: 574 ± 274 µm vs. 258 ± 100 µm; and CEREC: 1356 ± 1023 µm vs. 110 ± 49 µm). This was also true for deviations in rotation and angulation. The conventional impression showed an advantage only regarding the absolute 3D deviation compared to the older systems. Based on the data of the present study, the accuracy of intraoral scanners is decisively related to hardware and software; though, newer systems or software do not necessarily warrant improvement. Nevertheless, to achieve high transfer accuracy, regular updating of digital systems is recommended. The challenge of increasing errors with increasing scan paths is overcome in the most recent systems. The combination of two different scanning principles in a single device seems to be beneficial.
Highlights
This may be related to inherent limitations when using only one scanning principle, which can only be overcome by combining several scanning principles
In contrast to the best-fit method, this approach made it possible to obtain an accurate 3D interpretation of the results. This approach, requires an reference cube (RC) or another reference structure, which is only achievable in an in vitro setup. Though this prerequisite is a clear limitation for clinical studies, it is a strength of the present study, as we aimed to compare the different scanners in families with the utmost precision
The scanning accuracy of Intraoral scanners (IOSs) is decisively related to hardware and software version; though, newer systems or software versions do not necessarily warrant improvement
Summary
Numerous studies on IOS are available, most dealing with different aspects of accuracy, some addressing handling, and a few focusing on the further development and implementation of digital processes [3,4,5,6,7]. All these aspects are necessarily related to the capabilities of the actual scanners used in this study [8]. As only a single scanner family uses active wavefront sampling, this family is included, the respective manufacturer will discontinue the scanner and the future of the system is unclear
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
