This is an example of what Appliance Whitening can accomplish.
As you can see, the before photo demonstrates heavily discolored teeth. After two weeks of Appliance Whitening, much of the color has been lightened substantially. The color near the gumline of the teeth has also lightened, although not as much as the color in the middle of the tooth or near the biting edge of the tooth. This is a common characteristic of any whitening process. Color gradation from the neck of the tooth to the biting edge is also naturally found on teeth which have never been whitened.