J Adv Prosthodont.  2018 Dec;10(6):422-429. 10.4047/jap.2018.10.6.422.

In vitro evaluation of color and translucency reproduction of maxillofacial prostheses using a computerized system

• Karakoca Nemli S
• BankoÄŸlu Güngör M
• BaÄŸkur M
• Turhan Bal B
• Kasko Arıcı Y

• KMID: 2429375
• DOI: http://doi.org/10.4047/jap.2018.10.6.422

Abstract

PURPOSE
Accurate color matching of maxillofacial prostheses to skin is important for esthetics. A computerized color matching system specific to human skin has recently been developed. The purpose of this study was to evaluate the accuracy in color and translucency matching of the computerized color matching system across different skin colors.
MATERIALS AND METHODS
The silicone was colored to simulate 28 different skin colors (n=5) to serve as "target skin colors". Using a spectrocolorometer (e-skin), color codes were determined for "replicate skin color" fabrication. CIELAB Delta-E between target skin color-replicate skin color pairs and translucency parameter were calculated. CIELAB Delta-E values were compared with one-way ANOVA and Tukey multiple-comparison. The agreement between L*, a*, b* and translucency parameter of target skin colors and replicate skin color were calculated by a two-way mixed average measures intraclass correlation coefficient. Translucency parameter of target skin color-replicate skin color pairs were compared with Paired t-test (α=.05).
RESULTS
The mean CIELAB Delta-E value was 3.83 and significant differences were found among colors. The intraclass correlation coefficient showed excellent reliability for L*, a*, b* and good reliability for translucency parameter (P < .001). The mean translucency parameter of replicate skin colors was significantly higher than that of translucency parameter.
CONCLUSION
The computerized color matching system specific to human skin was found to be reliable in terms of color and translucency between target skin colors and replicate skin color.

Keyword

Silicones; Color; Pigmentation

MeSH Terms

Esthetics
Humans
In Vitro Techniques*
Maxillofacial Prosthesis*
Pigmentation
Reproduction*
Silicon
Silicones
Skin
Skin Pigmentation
Silicon
Silicones

Figure

• 

  Fig. 1 The pigments used for 28 Target Colors and one specimen for each Target Color.

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  Fig. 2 Four steps of obtaining the recipe for a specimen (Specimen C25-1) using e-skin system (1) Measuring the specimen using spectrocolorometer and obtaining its color code (2) Finding E-skin system's on-line calculator (3) Entering the color code into calculator (4) Obtaining the recipe for a desired amount of silicone.

• 

  Fig. 3 Mean CIELAB Delta-E values and standard errors of the means calculated for each target color-replicate color pair groups.

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