GC EUROPE G-aenial - Manual (Page 8)

8 G-ænial Anterior & Posterior Technical Manual
5.0 Shades
5.1 introduction
One of the biggest challenges in prosthetic and restorative dentistry is to reproduce mother
nature’s well balanced tooth colour harmony. Patients demand restorations that equal or surpass
the aesthetics of nature and that are indiscernible from the tooth structure. One of the main
objectives in developing G-ænial was to create a state-of-the-art composite that would offer
predictable aesthetics in both simple and complex situations. With G-ænial, it is possible for the
clinician to balance dental science and the artistry of a patient’s smile.
It is not only about translucency, value, hue and chroma…
colour depends on three factors: the colour (hue), the saturation of the colour (chroma) and the
lightness/darkness of the colour (value). in dentistry, a fourth factor, translucency, is equally important.
Translucency is defined as the property to allow light to pass through, but only diffusely; as a result,
an object on the other side is not clearly distinguishable. Opaque materials are not translucent.
translucency of a composite material is necessary to adjust the value of the restoration to that of
the natural tooth and avoid a non-aesthetic opaque result. however, restoration thickness will vary
in a cavity, giving more or less translucency. light reflection will also differ depending on the angle
from which the restoration is observed. therefore, it can be assumed that translucency and
variations in opacity alone will not result in a chameleon effect.
The natural reflection of light from the tooth determines the colour observed by the human eye.
When we look at a tooth, reflected light is observed that consists mainly of mirror and diffused
reflection. Mirror reflection determines the quality of the gloss, while we “feel” the hue, chroma,
value and translucency from diffusively reflected light.
Figure 3: transmission, Fluorescence and reflection of light on the
tooth structure. courtesy mr. F. Feydel and Dr. e. D’incau, France
Figure 4: light reflection of a natural tooth varies
according to the diverse refractive index of its
structure (enamel, dentin, enamodentinal
junction...)