Until fairly recently, if a dentist wanted to take a shade of tooth for restorative or record purposes, he or she was limited to taking a shade by matching a tooth to an established shade guide. This was done manually and thus subject to the vagaries of office lighting and the ambiguities of the human eye. Today, however, we have six systems that eliminate human error and can provide more predictable results. The systems currently available are Clear Match, Shade Scan, ShadeEye, Easy Shade, Shade Vision, and SpectroShade. All of the systems have drawbacks, and all besides Easy Shade and Clear Match are bulky. Clear Match adds (what I believe to be) error in that it requires taking a digital camera image (and thus is dependent on the pixilation of the camera). Only Easy Shade and SpectroShade employ spectrophotometry, which I believe to be the most accurate method of shade taking. The others employ digital interpretation of shade that then converts to the porcelain shade guide. The downside to Easy Shade will be explained later, and although I have not used all of the above systems, I am skeptical of their accuracy.
In a previous review of shade taking systems one system was not reviewed, the SpectroShade by MHT International.
From my approximately four years of experience with the SpectroShade, I believe it is the model that should be used as the standard when comparing shade taking systems because of its proven reliability in my office. My shade taking success rate with the unit exceeds 99% over several hundred cases, and even in those cases where the shade has been off, the base shade was always correct and only required limited custom staining with my lab technician. Thus, technically it has never given a bad shade.
The unit employs spectrophotometry to record the shade. The “guts” of the unit are enclosed within a PC and connected to the wand. Spectrophotometry measures light intensity and measures that intensity as a wavelength of light. The unit then converts that measurement into the Classic Vita Shade Guide. It provides either an overall shade (Figure 1) or the shade can be broken down into three distinct areas, cervical, middle, and incisal, and provide shades in each of these areas (Figure 2). Within each of the three areas, the unit will provide a mathematical formula resulting in a delta E (dE) (Figures 3, 3A, 4). According to the manufacturer, if that delta E is less than 1.0 then it represents a difference that is not discernable to the human eye. In addition, the unit within each segment will provide a relative intensity of hue going from left to right. While this can be significant information, usually I have found providing the shade breakdown by cervical 1/3, middle 1/3, and incisal 1/3, along with degree of incisal opacity, to be sufficient. For more difficult shades, this additional information can be shared with your lab technician and aid in custom staining. In short, this is a very reliable system. The downside to the system is that the size of shade wand is relatively large, such that the device is useful largely for the upper anterior teeth and sometimes for first and second bicuspids. There is a bit of a learning curve to master the technique, but it is relatively quick.
Other systems purport to use spectrophotometry (EasyShade, for example), but do not seem to work as well. I have personal experience with EasyShade; I tried to make this system work for more than five months without any success. The company sent me a replacement unit believing the first was defective; however, it was just as unreliable as the first. All shades recorded by the EasyShade were significantly different from the visual confirmation, usually darker. A representative form Vident finally came out to prove to me the system worked by taking a shade on himself. He emphatically stated that the shade recorded by the machine was accurate, so I held up the shade tab next to the tooth (a central incisor) and it wasn’t even close—he truly looked surprised when I handed him a mirror so that he could see for himself that the shade was incorrect!
What all of us want in any shade taking system is a simple, foolproof method of recording the shade and communicating that shade to our laboratories. Ideally, that system is also small, comfortable to the patient, and usable in all areas of the mouth. Realistically, however, it is the upper anterior teeth that usually dominate the smile zone and thus dictate shade. Thus, while it would be advantageous to have a system that can take shades on the upper left second molar, the information is largely superfluous. The SpectroShade System is not ideal, and it’s limited to recording the shade of the upper anterior teeth and perhaps the bicuspids in some cases. It is bulky, and it’s not always as comfortable to the patient as we would like. But it is the closest thing we can get to an objective shade taking system, and provides a record of that information and the necessary information to communicate the shade to the lab. In my office, though it has not eliminated the chairside custom shading that my lab does for me, it has greatly reduced the need for such services. Even when services are needed, the corrections are usually minor and confined to staining rather than correcting via an incorrect base shade. The end result is that this system gives you an edge over other dentists, impresses patients in that they see technology not available in most offices, and most importantly, reduces stress and saves time. It can even be used to record shades prior to in-office bleaching, and thus demonstrate and record shade changes. In my office, it is an invaluable tool that I would not do without today.
Review Synopsis
Product
SpectroShade
The Good
Accurate shade matching, good for marketing, permanent record of shades
The Bad
A bit costly, limited to use in the anterior region
The Bottom Line
The gold standard by which other systems should be judged and indispensable for cosmetic dentistry.