Cultivating the Skill of Shade Matching

Successful musicians, painters, and other artists are both gifted and well educated in their craft, and yet they continue to practice and improve their skills. In contrast, little effort is made to assess whether the average dental professional has an eye for shade matching. Moreover, education on color is frequently not even part of the undergraduate or graduate dental school curriculum.^1–3 Years of shade-matching experience practiced under inappropriate conditions, using inadequate tools and methods, can hardly be called color training. The literature shows that dentists often overestimate their color-matching and reproduction abilities. When asked to match 16 corresponding pairs from two Vitapan Classical shade guides using the visual method, the pre- and postdoctoral participants correctly matched only 50%.⁴ In another study, which closely resembled clinical dentistry in that there was no exact match, the observers’ choice was the second or third best match.⁵

Several surveys have been conducted on color education. The first one, in 1967, revealed that only 3 institutions (of the 115 institutions that responded) offered a color science course, and only 2.3 classes, on average, referred to color topics.¹ In another survey, core curriculum and elective courses on color were taught at 26% and 17%, respectively, of the 69 responding schools.² A third survey related to teaching of color in predoctoral and postdoctoral dental education was conducted in 1988. Responses were received from 138 institutions.³ The mean number of hours devoted to color topics was 6.6, and 50% of the schools reported a lack of a color-balanced environment. In addition, 85% of respondents believed that there was a need to develop a new, systematic shade guide. It was concluded that additional efforts should be made regarding the study, research, and application of color science in the dental profession, particularly in undergraduate education.

Currently Available Shade-Matching Publications and Programs

Several multimedia color education and training programs are now available (Table 1-1). Each program has its own unique features, but they all are designed with the same intention: to educate/train dental professionals in color matching. A brief description of each program is provided below.

The book Esthetic Color Training in Dentistry and its supplementary color-training exercises on CD-ROM are designed to be used by dental professionals, educators, and students. The training program consists of an introductory set, a training set, and an advanced set. The introductory and training sets each consist of three groups of exercises, which progress from easy to difficult. Each of these six different sets consists of 25 small squares and arranging sets that test shade matching based on differences in value, chroma, or hue, and, for further challenge, differences based on all possible pairs of color dimensions (value/chroma, value/hue, and chroma/hue). The advanced set (Fig 1-1) contains 15 rectangles with color differences that originate from all three color dimensions simultaneously.⁶ The software records both first and highest scores and includes a “reset score” option that enables repetition of the exercises or addition of other users.

TABLE 1-1 Shade-matching publications and programs

Fig 1-1 Color Training Exercises, advanced set.

Another popular multimedia program is the Toothguide Trainer software and Toothguide Training Box (Vita Zahnfabrik) (Figs 1-2 and 1-3), which are parts of the color-training program developed by Jakstat.⁷ The exercises in the training software are essentially the same as those in the training box; both utilize 26 shade tabs from the Toothguide 3D-Master (Vita Zahnfabrik). The software uses the images of tabs, whereas the training box uses physical shade tabs, along with color-corrected light and computer support. The program is designed in accordance with the three-step method recommended for 3D shade-matching (value-chroma-hue selection). A total of 4, 8, and 15 correct matches, respectively, are needed to pass steps 1 (value selection), 2 (value-chroma selection), and 3 (value-chroma-hue selection). After that, the user proceeds to 15 value–chroma–hue tasks in the final exam.

A Contemporary Guide to Color & Shade Selection for Prosthodontics is a DVD published by the American College of Prosthodontists.⁸ It is a predominantly educational tool with 63 figures and 12 instructional videos that complement the text.

Fig 1-2 Toothguide Training Box with the associated computer program.

Fig 1-3 Toothguide Training Box with working area illuminated by color-corrected light.

In the first part, general color topics are addressed: color triplet, defective color vision, color mixing, the color wheel, a description of color and the relationship between the dimensions of color, and two color notation systems: Munsell and CIELAB. The second part of the text is related to the color of human teeth, dental shade guides, and digital shade selection.

The DVD also includes detailed guidelines for visual shade selection and suggested procedures and discusses:

• Light source parameters
• Type, amount, and location of lighting
• Metamerism
• Surrounding colors
• Shade-matching distance
• Time and length of shade selection
• Patient position and involvement
• Tooth condition, including light transmission and surface characteristics (texture and gloss)
• Translucency and transparency
• Dentin and gingival shade selection

Shade verification and communication with the dental laboratory technician using diagrams and digital images are also elaborated.

Finally, Dental Color Matcher (Vita Zahnfabrik) is a free online education and training program hosted through the website of the Society for Color and Appearance in Dentistry (www.scadent.org/dcm).⁹ This program is a combination of color matching exercises and a didactic video.

The first of the onscreen exercises, “Closest match I,” asks the user to determine the best match to four target shade tabs using Linearguide 3D-Master tabs (Fig 1-4). Afterward, the 25-minute video provides information on the role of color in contemporary esthetic and cosmetic dentistry, shade-matching skills and success of dental professionals, color dimensions and the color of human teeth, and color-matching methods used in dentistry. The video particularly addresses influences on the visual method, such as years in practice, sex, education and training, color-matching conditions, as well as techniques to achieve predictable success with visual shade matching.

Fig 1-4 Dental Color Matcher. “Closest match” exercise.

Fig 1-5 Dental Color Matcher. “Matching pairs” exercise: 14 darker pairs of shade tabs successfully matched.

After the video, users are prompted to “Matching pairs” exercises to match 29 Linearguide 3D-Master pairs (15 lighter pairs and 14 darker pairs) (Fig 1-5). The subsequent “Exact match exercise” is identical to the initial “Closest match” exercises, except that there is an exact match to each tab. The next step is a quiz in which users answer 12 multiple-choice questions related to the information provided in the video. After completing the program, users can fill out a survey, rate the program, and list its strengths and weaknesses. Upon request, dental professionals can obtain 2 continuing education hours, while all users obtain a diploma issued by the Society for Color and Appearance in Dentistry upon program completion. Dental educators who want to use this program for undergraduate or postgraduate teaching or continuing education for dental students or professionals are encouraged to request a project code (by sending an email to dcm@scadent.org), which will allow them to independently access the results for each enrolled participant.

Conclusions

Significant advances have been made in color education and training in dentistry. New books and other types of publications—training programs on CD-ROM, online programs, and those that utilize physical shade tabs—are currently available. Based on purpose and scope, all of these publications and programs offer valuable color education and/or training. Online programs provide free access to a wide range of users (clinicians, dental technicians, dental educators, students, and researchers) seeking color education and training. Knowledge and skills acquired through these programs complement the skills of dental professionals and provide an appropriate foundation for their work.

Summary

• Shade-matching results can be improved through color education and training.
• Most color education and training programs are relatively new, and unfortunately few are currently incorporated into undergraduate or graduate dental education. Therefore, the implementation of available programs and the development of new tools should be the next step in color education and training in dentistry.

References

1. Sproull RC. Color matching in dentistry. Part I. The three-dimensional nature of color. J Prosthet Dent 1973;29: 416–424.
2. O’Keefe KL, Strickler ER, Kerrin HK. Color and shade matching: The weak link in esthetic dentistry. Compendium 1990;11:116–120.
3. Goodkind RJ, Loupe MJ. Teaching of color in predoctoral and postdoctoral dental education in 1988. J Prosthet Dent 1992;67:713–717.
4. Okubo SR, Kanawati A, Richards MW, Childress S. Evaluation of visual and instrument shade matching, J Prosthet Dent 1998;80:642–648.
5. Paravina RD. Performance assessment of dental shade guides. J Dent 2009;37(Suppl 1):e15–20.
6. Paravina RD, Powers JM. Esthetic Color Training in Dentistry. St Louis: Mosby, 2004.
7. Haddad HJ, Jakstat HA, Arnetzl G, et al. Does gender and experience influence shade matching quality? J Dent 2009;37(Suppl 1):e40–e44.
8. Goodacre CJ, Paravina RD, Bergen SF, Preston JD. A Contemporary Guide to Color and Shade Selection for Prosthodontists [DVD]. Chicago: American College of Prosthdontists, 2009.
9. Dental Color Matcher training program. http://www.scadent.org/dcm. Accessed 10 February 2010.