Comparative Analysis of the Accuracy of Six Intraoral Scanners Using a Full-Arch Model

Abstract

Objective: This in vitro study aimed to evaluate the scan accuracy of 6 intraoral scanners (IOSs) by using a dentate model. Methods: A maxillary dentate reference model was digitized with an industrial-grade blue light optical scanner to generate a reference standard tessellation language (STL) file. The same model was digitized by using 6 IOSs (Trios 4, Trios 3, Primescan, Omnicam, Planmeca Emerald S, and Medit i700) (n=10) to generate test scan STLs. All STL files were imported into a 3-dimensional analysis software program (Geomagic Control X). Test scan STLs were superimposed over the reference STL by using the initial and best-fit alignments of the software program, and the deviations of the scans of IOS from that of the optical scanner were calculated with the root mean square (RMS) method. The average deviation method was used to define the precision of the scans. Kruskal-Wallis and Bonferroni tests were used to statistically evaluate the data (α=0.05). Results: A significant difference was observed between groups in terms of RMS values (p<0.001). The Medit i700 and Primescan IOS systems had the lowest RMS values, respectively, indicating the highest trueness. No significant difference was observed between the groups in terms of precision. (p=0.055) Conclusion: While differences were observed among the six intraoral scanners, the accuracy of the selected IOSs remained within the clinically acceptable ranges. The Medit i700 and Primescan IOS exhibited a higher level of precision in comparison to the other devices. The accuracy of the scanner should be assessed, taking into account clinician, patient, and IOS dependent variables.

Keywords

• digital impression
• intraoral scanner
• 3D analysis

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