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Updated: May 20, 2026
07:57
Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision
Published on: April 29, 2014
Accuracy of digital models obtained by direct and indirect data capturing.
Jan-Frederik Güth1, Christine Keul, Michael Stimmelmayr
1Department of Prosthodontics, Dental School of the Ludwig-Maximilians University Munich, Goethestraße 70, 80336, Munich, Germany. jan_frederik.gueth@med.uni-muenchen.de
Clinical Oral Investigations
|August 1, 2012
Summary
Direct digital scanning (Lava C.O.S.) offers superior accuracy for CAD/CAM restorations compared to indirect methods. This digital workflow improves impression accuracy for dental prosthetics.
Area of Science:
- Dental Materials Science
- Digital Dentistry
- Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM)
Background:
- Digital and indirect workflows offer distinct pathways for fabricating CAD/CAM restorations.
- Evaluating the precision of each step in these digital workflows is crucial for clinical success.
Purpose of the Study:
- To compare the accuracy of single steps in direct and indirect CAD/CAM workflows.
- To introduce a novel methodology for comparing construction datasets.
Main Methods:
- Generated 12 test datasets in vitro using Lava Chairside Oral Scanner (COS) for direct digitization.
- Digitized polyether impressions (IMP) and scanned gypsum casts (ST) using Lava Scan ST.
- Utilized inspection software and a best-fit algorithm to superimpose test datasets against a reference dataset from industrial computed tomography.
Main Results:
- Direct digitization (COS) yielded the highest accuracy (17 μm/-13 μm), followed by digitized impressions (IMP, 23 μm/-22 μm) and indirect scanning (ST, 36 μm/-35 μm).
- Mean absolute Euclidean distances were lowest for COS (15 μm), then IMP (23 μm), and ST (36 μm).
- Significant differences were found in mean negative and absolute values across all groups; IMP and COS showed no significant difference in mean positive values.
Conclusions:
- Direct digitization using Lava C.O.S. demonstrated statistically significant higher accuracy than conventional impression taking and indirect digitization.
- Direct digital impression methods show promise for enhancing the accuracy of impressions for four-unit fixed dental prostheses (FDPs).
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