In vitro Comparison of Accuracy of Two Scanners Used in Dental Medicine

Abstract

This experimental study aims to highlight and compare the resolution and accuracy (trueness and fidelity) of an intraoral scanner and a laboratory scanner. In order to achieve the aim of this study, an experimental model consisting of a die with a standard preparation for a porcelain-fused to metal crown was manufactured from a physiognomic polymethylmethacrylate resin. The experimental model was scanned with an industrial CT to obtain the virtual reference model. Then, the die was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. In regards to the trueness of the scanners, the average deviation for the laboratory scanner is 4.31 and 17.34 mm for the intraoral scanner. When comparing the serial scannings� of the same die, the lowest recorded deviation is 6.4 mm for the laboratory scanner and 21.57mm for the intraoral scanner. For both fidelity and trueness, the F test demonstrates that there is a statistically significant difference between the scanners and the applied T-tests confirm the lower degree of error-rate generation by the laboratory scanner. The dimensional limitations imposed for the intraoral scanners have a direct consequence on their trueness and fidelity when compared to their laboratory counterparts.

Virtual Models Obtained via Intraoral Scanning as Alternated to Clinical Evaluation and b-Hemihydrate Plaster Models

“…The accuracy of the digital measurements of gingival margins was evaluated by the two parameters described by the ISO standard 5725-1 [9]: trueness -referring to the existing deviation between the real dimension of the measured object and the measurement result itself -and precision -referring to the repeatability of the measurements [10,11].…”

Virtual Models Obtained via Intraoral Scanning as Alternated to Clinical Evaluation and b-Hemihydrate Plaster Models

“…The accuracy of the digital measurements of gingival margins was evaluated by the two parameters described by the ISO standard 5725-1 [9]: trueness -referring to the existing deviation between the real dimension of the measured object and the measurement result itself -and precision -referring to the repeatability of the measurements [10,11].…”