CIE L*A*B* VALUES IN VITA CLASSICAL AND VITA 3D MASTER BY TWO DENTAL SPECTROPHOTOMETERS

Purpose: To compare the CIE L*a*b* values of two different dental shade guides using two shade-matching spectrophotometers. Materials and Methods: SpectroShade Micro (SS) and Easyshade (ES) (VITA Zahnfabrik) were tested. One calibrated operator performed 30 measurements of each tab from three batches of the two guides, VITA Classical (VC) and VITA 3D Shade Master (VM). Receiver operaNng characterisNc (ROC) curves and intraclass coefficients (ICC) between the different batches were calculated. Results were given as mean and SD of the L*a*b* values and the respecNve color differences according to the CIEDE 2000 formula (Delta E-00) for each of the shade tabs in the two spectrophotometers and then analyzed with independent student t test (alpha = .05). Results: A total of 1,440 and 2,610 measurements for VC and VM, respecNvely, were performed per spectrophotometer. There were staNsNcally significant differences between the two devices for all L*a*b* values, with the excepNon of: L* for 3R1.5; a* for 2R1.5, 3L1.5, 2L2.5, 3M2, 3L2.5, 4L1.5, and 4L2.5; and b* for D3, 1M2, and 3M2. When assessing the same shade guide, differences in.E00 were detected between devices above the acceptability threshold (AT) (Delta E-00 >= 1.8) for all shade tabs except for VC (C1, C2, D3, A3.5, C3, and A4) and VM (4M1, 3R2.5, 4L2.5, and 4M3). The overall mean of the interdevice Delta E-00 was 2.2 +/- 1.0 for VC and 2.5 +/- 1.0 for VM. Conclusions: The two dental spectrophotometers presented high ICC and ROC values, which validates their indicaNon as auxiliary tools. However, there are discrepancies in the hues D (VC) and R (VM) with interdevice variability when evaluated for the L*a*b* component.