Jeffrey B. Dalin, DDS, FACD, FAGD, FICD
What you want in a system like this is a carefully tailored illumination source, high-accuracy color filtration, and tailored image-processing algorithms.
The longer I practice dentistry, the more I realize that dentistry is every bit as much an art as it is a science. Color is something we work with on a daily basis. We are constantly matching surrounding tooth structure with composite restorations by layering different shaded materials to give them vibrancy. We have numerous porcelain systems available for our use when our laboratory technicians are called to action. We desire aesthetic excellence ... and our patients demand it!
Color can be scientifically defined by three attributes:
- Hue, or the classifying color used - red, blue, green, etc.
- Value, or the lightness or darkness of the color
- Chroma, or saturation or vividness of the color - dullness to brightness of the color
What one person perceives is not necessarily what another person sees. Surrounding conditions - such as lighting and background colors in the area - play a huge role in how we interpret color.
Errors in shade selection can occur in any one of four areas:
- Selecting the shade: This is where human color perception and surrounding conditions come into play.
- Reporting the shade that you have selected: This is where we try to map out exactly how the shades vary within the tooth that we are trying to duplicate.
- Interpretation of the prescription that we send in to our labs: Technicians often have trouble figuring out what we have described and written out.
- Fabrication of the ceramic restoration: We frequently find small value or chroma errors here that make a big difference in the final aesthetic results of the case. We now have tools at our disposal that can help take some of the subjectivity out of color selection. Computerized, handheld devices are used to interpret colors and provide a shade map for the dental laboratory technician to use when fabricating ceramic restorations .
Some of these products currently available for our use are the X-Rite Shade Vision System, the Shofu ShadeEye System, the Cynovad ShadeScan System, and the Clear Match system. Other manufacturers are planning on coming out with similar systems in the not- too-distant future.
The advantages of these units are:
- Ease of use
- Full portability
- Remakes reduced because crowns are created with accurate, objective data.
Each system varies in that each has a different way of creating its shade-match data. What you want in a system like this is a carefully tailored illumination source, high- accuracy color filtration, and tailored image-processing algorithms. I recommend trying as many of the different units as possible, until you find one that works well in your hands and in the hands of your laboratory technician.
We have rulers to measure length. We have scales to measure weight. Shouldn't we use something that accurately measures tooth shade and translate this measurement into a naturally beautiful restoration?
Jeffrey B. Dalin, DDS, FACD, FAGD, FICD, practices general dentistry in St. Louis. He also is the editor of St. Louis Dentistry Magazine and spokesman and critical-issue-response-team chairman for the Greater St. Louis Dental Society. His address on the Internet is www.dfdasmiles.com. Contact him by email at email@example.com, by phone at (314) 567-5612, or by fax at (314) 567-9047.