Accuracy of Three Shade-matching Devices in Replicating the Shade of Metal Ceramic Restorations: An in vitro Study

Abstract

In restorative dentistry, the clinician commonly encounters the challenge of replicating the color of natural teeth due to the subjectivity of perceptual evaluation. Recent advances in photography and computing have resulted in the widespread use of the digital camera for color imaging. These instruments can be used effectively for shade matching and communication to yield predictable results. The study sample consisted of 20 freshly extracted noncarious premolars. The Commission Internationale de l'Eclairage (CIE) L*a*b* values of the tooth were obtained through a spectrophotometer, digital camera, and digital camera with a polarizer. Shade selection was carried out using VITA 3D Master and calculating the Euclidian distance. The fabricated metal ceramic crowns were then evaluated to check the shade replication by comparing the CIE L*a*b* values of the crowns with the reference shade tab images. The three-way analysis of variance (ANOVA) and comparative analysis using Bonferroni test reveals that the difference in the mean L*a* values between spectrophotometer and polarization dental imaging modality (PDIM) was insignificant. The difference in the mean L*a*b* of spectrophotometer and digital camera was statistically significant. The mean ΔE for metal ceramic crowns and shade tabs was 4.2 that was greater than the clinically acceptable level (3.2). A statistically significant correlation was found to exist between the spectrophotometer and PDIM for all CIE L*, a*, and b* color coordinates. The present study was undertaken to assess the shade-matching ability of three shade-matching devices, such as spectrophotometer, digital camera, and PDIM, in the accuracy of replication of metal ceramic restorations.