Performance Assessment of Digital Method for Skin Shade Measurement and Reproduction

Purpose. The purposes of this study were: to compare spectral curves of skin shade tabs fabricated from the e-skin device and traditional anaplastology method against non-contact spectroradiometer measurements of human skin at the same position; and to clinically evaluate both methods of shade reproduction in terms of color match using two blinded clinical evaluators.;Materials and Methods. 48 human subjects presented to the Houston Center for Biomaterials and Biomimetics (HCBB) and had their skin color measured by a spectroradiometer and a handheld colorimeter (e-Skin, Spectromatch London). They also had their skin color reproduced by a professional anaplastologist according to the subjective method of color reproduction. The measurements from the colorimeter were used to calculate a formulation for shade reproduction. Two sets of silicone specimens were made, one for the traditional method and one for the digital method. Each silicone specimen was then measured by a spectroradiometer. The resulting spectral curve data was converted to CIELAB values and used to calculate delta E* for the traditional method vs. subject, the digital method vs. subject, and the traditional method vs. the digital method. Two blinded evaluators performed a clinical evaluation. The evaluators were asked to answer a questionnaire pertaining to the color match of each silicone specimen to the subject's skin and also to the other silicone specimen.;Results. The delta E* values for the silicone specimens were found to be significant (p= 0.05). For the silicone specimens fabricated by the traditional method, the delta E* was 7.9. The delta E* for the silicone specimens fabricated by the e-Skin was 5.4. The delta E* between the traditional and e-skin specimens was 6.1.;The clinical evaluation found a perceptible difference between the traditionally fabricated silicone specimens and human subjects 91.7% of the time. The e-Skin silicone specimens were perceptibly different from the human subjects 86.5% of the time. The evaluators reported that this difference was clinically acceptable in 68.2% of the traditional specimens and 76.5% of the e-Skin specimens. A difference between the silicone specimens when compared to their counterparts was perceived 97.9% of the time. The evaluators reported that the e-Skin specimens matched the subjects 63.2% of the time while the traditional specimens matched 35.8% of the time.;Conclusion. The spectroradiometer comparisons showed that the e-Skin formulation resulted in a closer match to the human subject than the traditional anaplastology method. The clinical evaluation found that, for the majority of specimens, there was a visually perceptible difference regardless of method. A clinically acceptable match was possible with both methods, but happened more often with the e-Skin method. The e-Skin method resulted in a closer color match two-thirds of the time.