Statement of problem
In restorative prostheses, color is important, but the choice of color difference formula used to quantify color change in acrylic resins is not straightforward.
The purpose of this in vitro study was to choose a color difference formula that best represented differences between the calculated color and the observed imperceptible to unacceptable color and to determine the corresponding perceptibility and acceptability threshold of color stability for denture base acrylic resins.
Material and methods
A total of 291 acrylic resin denture base plates were fabricated and subjected to radiation tests from zero to 42 hours in accordance with ISO 7491:2000. Color was measured with a portable spectrophotometer, and color differences were calculated with 3 International Commission on Illumination (CIE) formulas: CIELab, CMC(1:1), and CIEDE2000. Thirty-four observers with no deficiencies in color perception participated in psychophysical perceptibility and acceptability assessments under controlled conditions in vitro. These 2 types of assessments were regressed to each observer by each formula to generate receiver operator characteristic (ROC) curves. Areas under the curves (AUCs) were then calculated and analyzed to exclude observers with poor color discrimination. AUCs were subjected to 1-way ANOVA (α=.05) to deter the statistical significance of discriminability among the 3 formulas in terms of perceptibility and acceptability judgments. Student-Newman-Keuls tests (α=.05) were used for post hoc comparison.
CMC(1:1) and CIEDE2000 formulas performed better for imperceptible to unacceptable color differences, with corresponding CMC(1:1) and CIEDE2000 values for perceptibility of 2.52 and 1.72, respectively, and acceptability thresholds of 6.21 and 4.08, respectively.
Formulas CMC(1:1) and CIEDE2000 possess higher discriminability than that of CIELab in the assessment of perceptible color difference threshold of denture base acrylic resin. A statistically significant difference exists between perceptibility and acceptability thresholds for denture base acrylic resin.
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Journal of Prosthetic Dentistry
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
- Color stability of resins and nylon as denture base material in beverages.J Prosthodont. 2011; 20: 632-638
- Assessment of surface hardness of acrylic resins submitted to accelerated artificial aging.Minerva Stomatol. 2012; 61: 283-288
- Esthetic color training in dentistry.Elsevier Mosby, St Louis2004: 17
- Colorimetry—technical report. CIE publication no. 15.3rd ed. Bureau Central de la CIE, Vienna2004
- Testing uniform colour spaces and colour-difference formulae using printed samples.Color Res Appl. 2012; 37: 326-335
- Suprathreshold color-difference ellipsoids for surface colors.Color Res Appl. 1997; 22: 148-155
- Modification to the JPC79 color difference formula.Journal of the Society of Dyers and Colourists. 1984; 100: 128-132
- CIE technical report: industrial color-difference evaluation. CIE pub no 116.CIE Central Bureau, Vienna, Austria1995
- The development of the CIE 2000 colour-difference formula: CIEDE2000.Color Res Appl. 2001; 26: 340-350
- Applicability of CIELAB/CIEDE2000 formula in visual color assessments of metal ceramic restorations.J Dent. 2012; 40: e3-e9
- Evaluation of polymerization-dependent changes in color and translucency of resin composites using two formulae.Odontology. 2005; 93: 46-51
- Influence of porcine liver esterase on the color of dental resin composites by CIEDE2000 system.J Biomed Mater Res B Appl Biomater. 2005; 72: 276-283
- Use of a porcelain color discrimination test to evaluate color difference formulas.J Prosthet Dent. 2007; 98: 101-109
- Perceptibility and acceptability thresholds for colour differences in dentistry.J Dent. 2014; 42: 637-644
- Assessment of perceptibility and acceptability of color difference of denture teeth.J Dent. 2012; 40: e10-e17
- Color difference thresholds of maxillofacial skin replications.J Prosthodont. 2009; 18: 618-625
- Color difference thresholds in dental ceramics.J Dent. 2010; 38: e57-64
- Intraoral determination of the tolerance of dentists for perceptibility and acceptability of shade mismatch.J Prosthet Dent. 2007; 97: 200-208
- Colour stainability of indirect CAD-CAM processed composites vs. conventionally laboratory processed composites after immersion in staining solutions.J Dent. 2014; 42: 831-838
- Color acceptance of direct dental restorative materials by human observers.Color Res Appl. 2000; 25: 278-285
- An experiment in visual scaling of small color differences.Color Res Appl. 1979; 2: 83-91
- Assessment of appearance match by visual observation and clinical colorimetry.J Dent Res. 1989; 68: 819-822
- Dental ceramics: a CIEDE2000 acceptability thresholds for lightness, chroma and hue differences.J Dent. 2011; 39: e37-e44
International Organization for Standardization. ISO 7491:2000. Dental materials—determination of colour stability. Geneva: ISO. Available at: http://www.iso.org/iso/store.htm. Accessed September 4, 2014.
- Colour vision test.2nd ed. People’s Public Medical Publishing House, Beijing2001: 1-66
- The interpretation of diagnostic tests.Stat Methods Med Res. 1999; 8: 113-134
- Parametric effects in colour-difference evaluation. CIE pub no. 101.CIE Central Bureau, Vienna, Austria1993
- Visual evaluation at scale of threshold to suprathreshold color difference.Color Res Appl. 2005; 30: 198-208
- Sensitivity differences in chroma, hue, and lightness from several classical threshold datasets.Color Res Appl. 1995; 4: 220-225
Published online: August 12, 2015
© 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.