I wrote this article for ArticlesBase in August of 2008 and it is still getting hits! It is a simple way to whiten the teeth in an image using Photoshop. I thought it would be helpful to reproduce it here and spread the info to more people. Hope it helps!
There is nothing quite so disconcerting as yellowish or gray teeth in your portraits! As an example you get a really good shot of your favorite “model” and when you look at the image in Photoshop you notice her teeth are a muddy white with a yellowish cast. Even if her teeth are less than perfect in real life, you can add extra snap and sparkle to the image by giving her a bright clean smile!
Open your image in Photoshop CS or Elements. I have made this simple so am not using Layers. Just make a copy of your image to work on.
In your Toolbox on the left, choose the Lasso tool. Along the top of the page you will see “feather” – set that to about 10% as it will soften the edge between the lightened teeth and the lips or gums. Now using the Lasso tool select just the teeth. There should be a “marching ants” line around them now. Work on this selection to make sure you are satisfied with it and that it covers all of the teeth, even the ones in the back.
Now you have the teeth selected, go to the top toolbar where it says “Image”. There is a pull-down menu. Select “Adjustments” and then “Brightness/Contrast” from that menu. Use the “Brightness” slider bar to increase the lightness of the teeth to where you think they look natural, and then press “OK”. Check out the overall effect of what you have done to see if it is satisfactory.
The next step would be to de-saturate any color cast such as a yellowish or sometimes pinkish tones on the teeth. You should still have the teeth selected. Go to the “Image” tab again, click on “Adjustments” and then “Hue/Saturation”. Take the Saturation slider and move it to the left, de-saturating the color from the teeth to a more neutral gray tone. You can also use the “Hue” slider to get a more pleasing tone to your finished product. Press “OK”
A final step would be to go to the Toolbox again on the left and click on the “Dodge” tool. Set it to a soft edged brush at about 10% exposure and click on “Highlights” in the “Range” menu on the top toolbar. Gently whiten the central area of each tooth to make a realistic roundness to each tooth. This can make the teeth look more natural. The teeth are still selected so you go up to “Select” on the top toolbar and then use the “Deselect” from that pull-down menu. This will turn off the selection leaving your adjustment to the teeth still in effect. Save your file!
This small touch on just the teeth of the subject can make a major difference in the appearance of the subject and she will be much happier with the result!