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Fundamentals of Esthetic Implant Dentistry
Figure 11.6. In Munsell’s color wheel, color is described in terms of hue, chroma, and value. Reproduced by permission of Quintessence Publishing, copyright Quintessence.
Figure 11.7. Various levels of translucency are exhibited by the natural dentition. Translucency is defined as the amount of transmitted light that passes through an object. The perception and quantification of translucency still remains elusive in dentistry. Reproduced by permission of Quintessence Publishing, copyright Quintessence.
these dimensions should be added translucency, which is not addressed in Munsell’s color analysis but is perhaps the most critical factor in the quest for an esthetic restoration. The four dimensions of color are defined as follows: 1. Hue: Synonymous with the term color. Used to describe the pigments of a tooth or dental restoration (e.g., red, blue, or yellow). 2. Value: The relative brightness of the hue. The scale of value ranges from 0 for pure black to 10 for pure white. 3. Chroma: The intensity or saturation of the color tone (hue). The closer the color is to a gray tone, the lower its chroma. Trained laboratory technicians generally can determine value and hue when presented separately. However, difficulties arise when value and chroma are coupled, and inconsistencies often occur when value determinations are made for dental restorations (Chu 2002b).
4. Translucency: The degree to which light is transmitted rather than absorbed or reflected. The highest translucency is defined as transparency (i.e., all light is transmitted), while the lowest is opacity (i.e., all light is reflected or absorbed). The incisal edges of natural teeth are translucent, and accurate translucency determination is vital to a restoration’s esthetic success. (See Figure 11.7.) A mistake in translucency greatly compromises the natural appearance of a restoration.
Elements Affecting Color There are many variables that affect how a color is perceived. These can be external (environmental) or internal (physiological). For example, the color of the sky cannot carry a blanket description of blue. The sky appears to be a different color in the morning than it does at midday or evening, with varying hues at different levels of relative lightness and brightness. The sur-