A successful restorative outcome should be evaluated under varying lighting conditions that are representative of the social environments and activities of the patient. Shade matching procedures, therefore, should be performed under daylight close to a window, as well as under room or ambient light in the operating environment.
Value is one of the three basic color parameters and is related to brightness (ie, to the degree of white and black) (Figure 25).
The color of a cross-polarized photograph is converted to a gray scale image by using a generic software program, such as Adobe Photoshop®.
The value of the restoration may be comparatively determined during the shade matching procedure and corrected if necessary within the restorative phase.
Chromatic Charting or Mapping
Shade matching98-104 between natural teeth and composite materials is the primary objective when creating direct restorations. This involves shade or chromatic mapping, which aims at identification of shade distribution, revealing important color information in two dimensions. Identifying dentin areas of diverse gradation in hue and chroma, the configuration and architecture of the lobes, bluish opalescence, and regions of intense hue are related to this.
Cross-polarized reflective capturing technique is considered the application of choice for chromatic mapping. The cross-polarized technique was described for both analog and digital cameras many years ago.105 Polarized photographs eliminate specular reflections of the flash, which makes identifying shade distribution easier. The photographic equipment is the same (camera body, macro lens, macro flash), but an additional polarizing filtering system is needed. A polarizing membrane sheet is placed in front of the flash lamp, covering the surface. For both the ring flash and twin light, the piece of membrane is split in two to cover the left and right flash lamps, always maintaining the orientation of the sheets parallel to each other. Another piece is placed perpendicular to the other sheets in front of the lens. In this way, the pieces are cross-polarized against each other, creating a matte photographic image (Figure 26).
Accurate chromatic mapping is an essential step for the overall successful shade matching between natural teeth and composite materials.
The present clinical report describes a comprehensive approach in documenting the optical properties of both dental restorative materials and natural hard dental tissues. Based on this concept, a simple and straightforward procedure is outlined and may be used during the restorative phase. In this way, documentation can take place in three different yet equally important time intervals: before, during, and after the restorative session. In direct adhesive procedures, such a concept is useful in refining the optical properties of the restorative materials, increasing the esthetic success rate of the restorative procedure.
Clinicians generally are familiar with the equipment and basic photographic techniques and are relatively confident working with digital cameras and dental photography. Updating the indications, optimizing the use of existing equipment, and decreasing overall costs were among the main goals of the authors. The photographic applications are explained in detail and clinicians can use them with any digital camera and flash system. Commercially available polarizing membrane sheets (linear polarizing film sheet) are very inexpensive and ideally suited for the cross-polarizing application. UVA 365-nm glass filters (eg, Schott® Optical Filters, us.schott.com) of 2-mm thickness are available in the market and are indicated for the recording of fluorescence. LED sources for transillumination (eg, Microlux) and LED illumination devices with different light temperatures (eg, Rite Lite 2) are available in the market and may be used for metamerism, translucency, and red-yellowish opalescence. The latter LED device, even though initially intended for clinical application only, can be easily adjusted in front of the digital camera lens for static no-flash pictures.
The described protocol of comprehensive documentation of the optical properties aims to determine differences between composite materials and natural tissues. Practitioners should be able to expand their knowledge of the shade-matching process and learn to distinguish the color elements that can and cannot be controlled during the restorative phase. Hue, chroma, metamerism, translucency, and red opalescence are inherent properties of restorative materials that may be diagnosed but which may not be influenced during the fabrication of direct restorations when a given brand of a composite material is used. On the other hand, value, bluish opalescence, and fluorescence are all considered inherent properties of the restorative materials that may be diagnosed and refined during the layering of materials in direct restorative procedures.
Within the limits of this clinical report, some conclusions can be drawn. Comparative level of luminosity, fluorescence, opalescence, translucency, and metamerism between natural tissues and dental materials may be recorded in daily practice by any clinician by using low-cost equipment based on a simple DSLR camera combined with inexpensive, commercially available add-on equipment. For direct restorations particularly, color elements that influence the overall restorative outcome, such as luminosity, fluorescence, and bluish opalescence, may be optimized because of correct diagnosis during the layering technique.
About the Authors
Yiannis Brokos, DDS, MSc, Dr. med. dent.
Division of Cariology and Endodontology
University Clinics of Dental Medicine
University of Geneva
Minos Stavridakis, DDS, MSc, Dr. med. dent.
Division of Cariology and Endodontology
University Clinics of Dental Medicine
University of Geneva
Ivo Krejci, Prof. Dr. med. dent.
Chairman and Professor
Division of Cariology and Endodontology
University Clinics of Dental Medicine
University of Geneva
1. Miller LL. Shade matching. J Esthet Dent. 1993;5(4):143-153.
2. Tripodakis AP. Shade selection in fixed prosthodontics. Odontostomatol Proodos. 1989;43(6):539-548.
3. Okubo SR, Kanawati A, Richards MW, Childress S. Evaluation of visual and instrument shade matching. J Prosthet Dent. 1998;80(6):642-648.
4. Lagouvardos PE, Diamanti H, Polyzois G. Effect of individual shades on reliability and validity of observers in color matching. Eur J Prosthodont Restor Dent. 2004;12(2):51-56.
5. Clary JA, Ontiveros JC, Cron SG, Paravina RD. Influence of light source, polarization, education, and training on shade matching quality. J Prosthet Dent. 2016;116(1):91-97.
6. Pecho OE, Pérez MM, Ghinea R, Della Bona A. Lightness, chroma and hue differences on visual shade matching. Dent Mater. 2016;32(11):1362-1373.
7. Clark EB. An analysis of tooth color. J Dent Am Assoc. 1931;18(11):2093-2103.
8. Saleski CG. Color, light, and shade matching. J Prosthet Dent. 1972;27(3):263-268.
9. Sproull RC. Color matching in dentistry. II. Practical applications of the organization of color. J Prosthet Dent. 1973;29(5):556-566.
10. ten Bosch JJ, Coops JC. Tooth color and reflectance as related to light scattering and enamel hardness. J Den Res. 1995;74(1):374-380.
12. Sproull RC. Color matching in dentistry. Part I. The three-dimensional nature of color. 1973. J Prosthet Dent. 2001;86(5):453-457.
13. Joiner A. Tooth colour: a review of the literature. J Dent. 2004;32(suppl 1):3-12.
14. Risnes S, Peterkova R, Lesot H. Distribution and structure of dental enamel in incisors of Tabby mice. Arch Oral Biol. 2005;50(2):181-184.
15. He LH, Swain MV. Understanding the mechanical behaviour of human enamel from its structural and compositional characteristics. J Mech Behav Biomed Mater. 2008;1(1):18-29.
16. Myoung S, Lee J, Constantino P, et al. Morphology and fracture of enamel. J Biomech. 2009;42(12):1947-1951.
17. Li R, Ma X, Liang S, et al. Optical properties of enamel and translucent composites by diffuse reflectance measurements. J Dent. 2012;40(suppl 1):e40-e47.
18. Willems G, Noack MJ, Inokoshi S, et al. Radiopacity of composites compared with human enamel and dentine. J Dent. 1991;19(6):362-365.
19. Joiner A. Review of the effects of peroxide on enamel and dentine properties. J Dent. 2007;35(12):889-896.
20. Lee YK, Lu H, Powers JM. Measurement of opalescence of resin composites. Dent Mater. 2005;21(11):1068-1074.
21. Lee YK, Lu H, Powers JM. Changes in opalescence and fluorescence properties of resin composites after accelerated aging. Dent Mater. 2006;22(7):653-660.
22. Cho MS, Yu B, Lee YK. Opalescence of all-ceramic core and veneer materials. Dent Mater. 2009;25;(6):695-702.
23. Yu B, Lee YK. Difference in opalescence of restorative materials by the illuminant. Dent Mater. 2009;25(8):1014-1021.
24. Yu B, Lee YK. Comparison of stabilities in translucency, fluorescence and opalescence of direct and indirect composite resins. Eur J Esthet Dent. 2013;8(2):214-225.
25. Panzeri H, Fernandes LT, Minelli CJ. Spectral fluorescence of direct anterior restorative materials. Aust Dent J. 1977;22(6):458-461.
26. Monsénégo G, Burdairon G, Clerjaud B. Fluorescence of dental porcelain. J Prosthet Dent. 1993;69(1):106-113.
27. McLaren EA. Luminescent veneers. J Esthet Dent. 1997;9(1):3-12.
28. Lee YK, Lu H, Powers JM. Effect of surface sealant and staining on the fluorescence of resin composites. J Prosthet Dent. 2005;93(3):260-266.
29. Sant’Anna Aguiar Dos Reis R, Casemiro LA, Carlino GV, et al. Evaluation of fluorescence of dental composites using contrast ratios to adjacent tooth structure: a pilot study. J Esthet Restor Dent. 2007;19(4):199-206,207.
30. Lee YK, Powers JM. Color changes of resin composites in the reflectance and transmittance modes. Dent Mater. 2007;23(3):259-264.
31. Lim YK, Lee YK. Fluorescent emission of varied shades of resin composites. Dent Mater. 2007;23(10):1262-1268.
32. Park MY, Lee YK, Lim BS. Influence of fluorescent whitening agent on the fluorescent emission of resin composites. Dent Mater. 2007;23(6):731-735.
33. Figueiredo C, Silva AM, Figueiredo A, Azenba ME. Fluorescence of dental composite resins. Experimental Pathology and Health Sciences. 2012;6(1):11-14.
34. Lee YK. Changes in the translucency of porcelain and repairing resin composite by the illumination. Dent Mater. 2007;23(4):492-497.
35. Ilie N, Hickel R. Correlation between ceramics translucency and polymerization efficiency through ceramics. Dent Mater. 2008;24(7):908-914.
36. Woo ST, Yu B, Ahn JS, Lee YK. Comparison of translucency between indirect and direct resin composites. J Dent. 2008;36(8):637-642.
37. Yu B, Lee YK. Differences in color, translucency and fluorescence between flowable and universal resin composites. J Dent. 2008;36(10):840-846.
38. Yu B, Lee YK. Influence of color parameters of resin composites on their translucency. Dent Mater. 2008;24(9):1236-1242.
39. Azzopardi N, Moharamzadeh K, Wood DJ, et al. Effect of resin matrix composition on the translucency of experimental dental composite resins. Dent Mater. 2009;25(12):1564-1568.
40. Kim SJ, Son HH, Cho BH, et al. Translucency and masking ability of various opaque-shade composite resins. J Dent. 2009;37(2):102-107.
41. Arimoto A, Nakajima M, Hosaka K, et al. Translucency, opalescence and light transmission characteristics of light cured resin composites. Dent Mater. 2010;26(11):1090-1097.
42. Kürklü D, Azer SS, Yilmaz B, Johnston WM. Porcelain thickness and cement shade effects on the colour and translucency of porcelain veneering materials. J Dent. 2013;41(11):1043-1050.
43. Wang F, Takahashi H, Iwasaki N. Translucency of dental ceramics with different thicknesses. J Prosthet Dent. 2013;110(1):14-20.
44. Ozakar Ilday N, Celik N, Bayindir YZ, Seven N. Effect of water storage on the translucency of silorane-based and dimethacrylate-based composite resins with fibres. J Dent. 2014;42(6):746-752.
45. Awad D, Stawarczyk B, Liebermann A, Ilie N. Translucency of esthetic dental restorative CAD/CAM materials and composite resins with respect to thickness and surface roughness. J Prosthet Dent. 2015;113(6):534-540.
46. Kim HK, Kim SH, Lee JB, Ha SR. Effects of surface treatments on the translucency, opalescence, and surface texture of dental monolithic zirconia ceramics. J Prosthet Dent. 2016:115(6):773-779.
47. Manojlovic D, Dramićanin MD, Lezaja M, et al. Effect of resin and photoinitiator on color, translucency and color stability of conventional and low-shrinkage model composites. Dent Mater. 2016;32(2):183-191.
48. Shiraishi T, Watanabe I. Thickness dependence of light transmittance, translucency and opalescence of a ceria-stabilized zirconia/alumina nanocomposite for dental applications. Dent Mater. 2016;32(5):660-667.
49. Lee YK, Powers JM. Metameric effect between resin composite and dentin. Dent Mater. 2005;21(10):971-976.
50. Kim SH, Lee YK, Lim BS, et al. Metameric effect between dental porcelain and porcelain repairing resin composite. Dent Mater. 2007;23(3):374-379.
51. Vanini L. Light and color in anterior composite restorations. Pract Periodontics Aesthet Dent. 1996;8(7):673-682.
52. Dietschi D. Layering concept in anterior composite restorations. J Adhes Dent. 2001;3(1):71-80.
53. Dietschi D, Ardu S, Krejci I. The silent revolution in dentistry. In: Exploring the Layering Concepts for Anterior Teeth. Berlin: Quintessence Publishing; 2004:235-250.
54. Dietschi D, Ardu S, Krejci I. A new shading concept based on natural tooth color applied to direct composite restorations. Quintessence Int. 2006;37(2):91-102.
55. Vichi A, Fraioli A, Davidson CL, Ferrari M. Influence of thickness on color in multi-layering technique. Dent Mater. 2007;23(12):1584-1589.
56. Niu Y, Ma X, Fan M, Zhu S. Effects of layering techniques on the micro-tensile bond strength to dentin in resin composite restorations. Dent Mater. 2009;25(1):129-134.
57. Özcan M, Pekkan G. Effect of delay in layering on the incremental adhesion of indirect dental composite resins. Int J Adhes Adhes. 2012;39:15-20.
58. Khashayar G, Dozic A, Kleverlaan CJ, et al. The influence of varying layer thicknesses on the color predictability of two different composite layering concepts. Dent Mater. 2014;30(5):493-498.
59. Brokos J, Mantas D, Lagouvardos P, Mountouris G. Digital photography in dentistry. Hellenic Stomatological Review. 2003;47:653-665.
60. Gordon P, Wander P. Specialized equipment for dental photography. Br Dent J. 1987;162(9):346-359.
61. Wang K, Kowalski EJ, Chung KC. The art and science of photography in hand surgery. J Hand Surg Am. 2014;39(3):580-588.
62. Sagawara Y, Saito K, Futaki M, et al. Evaluation of the optimal exposure settings for occlusal photography with digital cameras. Pediatric Dental. 2014;24(2):89-96.
63. Schaaf H, Streckbein P, Ettore G, et al. Standards for digital photography in cranio-maxillo-facial-surgery - Part II: Additional picture sets and avoiding common mistakes. J Craniomaxillofacial Surg. 2006;34(6):366-377.
64. Ettore G, Weber M, Schaaf H, et al. Standards for digital photography in cranio maxillo-facial-surgery – Part I: Basic views and guidelines. J Craniomaxillofacial Surg. 2006;34(2):65-73.
65. Jacobson A. Mastering dental photography. Am J Orthod Dentofacial Orthop. 2002;122(3):335.
66. Krieger G. Photography in dentistry: theory and techniques in modern documentation. Am J Orthod Dentofacial Orthop. 2012;142(4):568.
67. Keys LG, Agar JA. Documentation of maxillomandibular relationships during dental photography. J Prosthet Dent. 2002;87(4):466.
68. Tung OH, Lai YL, Ho YC, et al. Development of digital shade guides for color assessment using a digital camera with ring flashes. Clin Oral Investig. 2011;15(1):49-56.
69. Sascha H, Bazos P, Guardix JT, Naves LZ. Beyond visible: exploring shade interpretation. In: Duarte S, Jr., ed. Quintessence of Dental Technology. Hanover Park, IL: Quintessence Publishing; 2014:37:199-211.
70. Bazos P, Magne P. Bio-emulation: biomimetically emulating nature utilizing a histo- anatomic approach; visual synthesis. Int J Esthet Dent. 2014;9(3):330-352.
71. Shore V, Pardee AB. Fluorescence of some proteins, nucleic acids and related compounds. Arch Biochem BioPhys. 1956;60(1):100-107.
72. Armstrong WG. Ultra-violet spectrophotometric estimation of dentine protein in solution. Arch Oral Biol. 1962;7(6):771-772.
73. Booij M, ten Bosch JJ. A fluorescence compound in bovine dental enamel matrix compared with synthetic dityrosine. Arch Oral Biol. 1982;27(5):417-421.
74. Armstrong WG. Fluorescence characteristics of sound and carious human dentine preparations. Arch Oral Biol. 1963;8(2):79-90.
75. Matsumoto H, Kitamura S, Araki T. Autofluorescence in human dentine in relation to age, tooth type and temperature measured by nanosecond time-resolved fluorescence microscopy. Arch Oral Biol. 1999;44(4):309-318.
76. Lee YK. Fluorescence properties of human teeth and dental calculus for clinical applications. J Biomed Opt. 2015;20(4):040901.
77. Armstrong WG. The presence of ultra violet absorbing material and its relation to fluorescence 'quenching' effects in carious dentine. Arch Oral Biol. 1963;8(2):223-231.
78. Foreman PC. The excitation and emission spectra of fluorescent components of human dentine. Arch Oral Biol 1980;25(10):641-647.
79. Hafström-Björkman U, Sundström F, ten Bosch JJ. Fluorescence in dissolved fractions of human enamel. Acta Odontol Scand. 1991;49(3):133-138.
80. Bachmann L, Zezell DM, da Costa Ribeiro A, et al. Fluorescence spectroscopy of biological tissues—a review. Appl Spectrosc Rev. 2006;41(6):575-590.
81. Ruttermann S, Ritter J, Raab WH, et al. Laser-induced fluorescence to discriminate between a dental composite resin and tooth. Dent Mater. 2007;23(11):1390-1396.
82. Zhang L, Nelson LY, Seibel EJ. Red-shifted fluorescence of sound dental hard tissue. J Biomed Opt. 2011;16(7):071411.
83. Queiroz RS, Bandeca MC, Calixto LR, et al. Influence of the light-curing unit, storage time and shade of a dental composite resin on the fluorescence. Laser Phys. 2010;20(7):1647-1653.
84. Kim HE, Kim BI. An in vitro comparison of quantitative light-induced fluorescence-digital and spectrophotometer on monitoring artificial white spot lesions. Photodiagnosis Photodyn Ther. 2015;12(3):378-384.
85. Meller C, Klein C. Fluorescence of composite resins: A comparison among properties of commercial shades. Dent Mater J. 2015;34(6):754-765.
86. Lee YK, Yu B. Measurement of opalescence of tooth enamel. J Dent. 2007;35(8):690-694.
87. Schmeling M, Maia HP, Baratieri LN. Opalescence of bleached teeth. J Dent. 2012;40(suppl 1):e35-e39.
88. Pecho OE, Ghinea R, do Amaral EA, et al. Relevant optical properties for direct restorative materials. Dent Mater. 2016;32(5):e105-e112.
89. Pop-Ciutrila IS, Ghinea R, Colosi HA, Dudea D. Dentin translucency and color evaluation in human incisors, canines, and molars. J Prosthet Dent. 2016;115(4):475-481.
90. Li Q, Xu BT, Li R, Wang YN. Spectrophotometric comparison of translucent composites and natural enamel. J Dent. 2010;38(suppl 2):117-122.
91. Mikhail SS, Schricker SR, Azer SS, et al. Optical characteristics of contemporary dental composite resin materials. J Dent. 2013;41(9):771-778.
92. Wyszecki G, Stiles WS. Color Science: Concepts and Methods, Quantitative Data and Formulae. 2nd ed. New York, NY: Wiley-Interscience; 2000.
93. Craig RG, Powers JM. Restorative Dental Materials. 11th ed. St. Louis, MO: Mosby; 2002.
94. Marcus RT. The measurement of color. In: Nassau K, ed. Color for Science, Art and Technology. Amsterdam, Netherlands: Elsevier; 1998:31-96.
95. O’Brien WJ. Double layer effect and other optical phenomena related to esthetics. Dent Clin North Am. 1985;29(4):667-672.
96. Leow ME, Ng WK, Pareira BP, et al. Metamerism in aesthetic prostheses under three standard illuminants-TL84, D65 and F. Prosthet Orthot Int. 1999;23(2):174-180.
97. Thornton WA. How strong metamerism disturbs color spaces. Color Res Appl. 1998;23(6):402-407.
98. Paravina RD, Johnston WM, Powers JM. New shade guide for evaluation of tooth whitening—colorimetric study. J Esthet Restor Dent. 2007;19(5):276-283.
99. Kourtis SG, Tripodakis AP, Doukoudakis AA. Spectrophotometric evaluation of the optical influence of different metal alloys and porcelains in the metal-ceramic complex. J Prosthet Dent. 2004;92(5):477-485.
100. Eves MG. Shade selection and value control. J Dent Technol. 2000;17(1):11-17.
101. Culpepper WD. A comparative study of shade-matching procedures. J Prosthet Dent. 1970;24(2):166-173.
102. van der Burgt TP, ten Bosch JJ, Borsboom PCF, Kortsmit WJPM. Color measuring devices. Dental Abstracts. 2008;53(5):255-256.
103. Chu SJ, Trushkowsky RD, Paravina RD. Dental color matching instruments and systems. Review of clinical and research aspects. J Dent. 2010;38(suppl 2):e2-e16.
104. Sarafianou A, Kamposiora F, Papavasiliou G, Goula H. Matching repeatability and interdevice agreement of 2 intraoral spectrophotometers. J Prosthet Dent. 2012;107(3):178-185.
105. Papazoglou E, Brokos J, Mountouris G. A method to capture polarized digital dental photographs. Italian Journal of Operative Dentistry. 2006;IV(1):45.