The accuracies of three intraoral scanners with regard to shade determination: An in vitro study

J Prosthodont. 2023 Jun;32(5):111-117. doi: 10.1111/jopr.13571. Epub 2022 Aug 10.

Abstract

Purpose: To compare the accuracies of three intraoral scanners for shade determination function in vitro, and to preliminarily investigate the shade-matching characteristics of the three intraoral scanners.

Materials and methods: The shade of the middle third region of each shade tab on the Vita Classical A1-D4 shade guide (VC) was measured with a spectrophotometer (Vita Easyshade V, VE) and three intraoral scanners, including CEREC Omnicam (OM), 3Shape TRIOS 3 (T3), and TRIOS 4 (T4). A conversion table between VC values and CIELAB values was established from the database of VE to analyze the trueness. The reproducibility of the instruments was then compared by repeating the measurements five times.

Results: The mean color difference for each instrument was highest in the OM, followed by the T4, and lowest in the T3 and VE, respectively. The L* and a* value for OM, and the b* value for T4, were significantly different from those for VE (p <0.05). The reproducibility of the instrument was highest in the VE (Fleiss' kappa: 0.95), followed by the T3 (Fleiss' kappa: 0.89), T4 (Fleiss' kappa: 0.87), and OM (Fleiss' kappa: 0.78).

Conclusions: Of the three intraoral scanners, the trueness was best on the T3. The reproducibility of all the instruments was excellent.

Keywords: intraoral scanner; shade guide; shade matching; spectrophotometer.

MeSH terms

  • Color
  • Prosthesis Coloring*
  • Reproducibility of Results
  • Research Design*
  • Spectrophotometry