Comparison of the Easyshade Compact and Advance in vitro and in vivo

The objective of this study was to evaluate the repeatability, inter-examiner and inter-device reliability, and accuracy of the new VITA Easyshade Advance (ES-A) spectrophotometer in comparison with the Easyshade Compact (ES-C). For the in vitro study, six porcelain disks of random shade mixtures were fabricated from VITA ceramic powders. To analyze the repeatability of the ES-C and ES-A, readings were obtained by one examiner for one porcelain disk and one shade tab (VITA 3D-Master). Measurements were repeated by two examiners to evaluate inter-examiner reliability. To assess accuracy, porcelain disks and shade tabs were measured with the ES-C and ES-A and by means of a spectroradiometer (SR). a dagger E values between the shade tabs and disks were calculated. Differences between devices were evaluated by use of univariate analysis. Reliability and accuracy of both devices were also tested in a clinical setting. The intra-class correlation coefficient (ICC) was calculated for all assessments of reliability. Good agreement was observed for replicate measurements (ICC > 0.9), for inter-examiner reliability of the ES-A and ES-C (ICC > 0.9), and for inter-device agreement (ICC > 0.9). Univariate analysis revealed that a dagger E values for the spectrophotometers were consistent (p = 0.783); spectroradiometrically measured a dagger E was comparable, but the mean value was smaller than that for the spectrophotometers (p = 0.004). Clinical inter-device agreement was acceptable to high (ICC > 0.777). The accuracy of the ES-A was higher than that of the ES-C (p = 0.001). Within the limitations of the experiment, the spectrophotometers tested enabled reliable and accurate measurement. In the clinical setting, however, the ES-A seems more accurate. ES-C and ES-A can be valuable tools for the determination of tooth colors. Because of their good reliability, they should especially be used for the assessment of tooth color changes over time.