How to Whiten Teeth in Photoshop

Retouching a portrait in a way that makes the model looking the best way possible AND maintaining still a natural look, can be a bit of a challenge. The following tutorial ‘How to whiten teeth in Photoshop’ will help you to achieve this in an easy to understand manner.
It was been written with Photoshop CS in mind, but will, most likely, also work with earlier versions and certainly with all newer ones. Again this is part of our photoshop for beginners series where we want to provide something useful for those who are just started in photoshop.
For advanced users, this might not be as useful. Before now grabbing the dodge tool and getting started, here one prerequisite that should be met before you start whitening teeth in Photoshop:

All corrections that affect the whole image, such as color, saturation, level and contrast, should be made first, before starting to edit and retouch more in detail.
The image below shows the source image with all above corrections made. As you see this portrait has two main problems, the slight yellow tint of the teeth and the gaps between some of them.

The first step is to duplicate the layer, you can name it whatever you want, but ‘teeth’ would be a good choice! Now the most important part of the whole process, selecting the part of the image you actually want to edit. Whilst magic wand, and relatives, are great for some tasks, here we need something a bit more sophisticated, the ‘quick mask’. To go into ‘quick mask mode’, simply click on the right of the two buttons that are circled in red in the image below. Double click it to adjust the color and transparency of the mask.
As I am retouching a portrait, the default color of ‘red’ is a bit of an unfortunate selection, so I changed that one to a nice green, in order to be able to see better what I am doing. The ‘quick mask mode’ allows to create an exact selection with the help of the brush tool, to save it and to reload it when necessary. This way you can make your selection once and try out a variety of adjustments, without the need to repeat the selection process over and over again.

To get started, select a smallish brush with 100% hardness and start to paint over the duplicated layer with it. Basically you want to paint over all teeth, but leave the gums and lips untouched. Mistakes are easy to correct, simply swatch background and foreground color and paint with the different color over your mistake.
If you look at the image above, you see that I have ‘masked’ around half of the teeth already with the rest still to do. Switching between masking, and unmasking and working at a high magnification of 200 to 400%, allows you to cover exactly the area you will want to work on later. When you are done, click Select > Save Selection and save your quick mask for future use. Switch now to Standard mode (left button of the two encircled ones) and click Select > Inverse in the main menu. I always feather my selections slightly to avoid harsh transitions, here I choose 0.5px as a value. You now should have your teeth nicely selected and feathered and the fun can start.
Go to Image > Adjustments > Hue / Saturation in the main menu and select ‘Yellow’ in the edit drop down menu. Reduce now saturation to about – 80 and click ok. Now switch to the dodge tool, located in the toolbox, and set to ‘Range: Midtones’ and ‘Exposure: 15%’. Don’t choose now a small brush, make the brush big enough to cover the whole, selected, area, and more.
As you are working on a selection, the tool will only affect this, but not the whole image. To whiten teeth in Photoshop, simply click with the oversized brush into the selected area, each click will brighten your selection up a bit more. Take care not to overdo it, unless you are working on a ‘whiter than white toothpaste ad’. When you are happy, deselect everything and admire your work.
Remember the gaps between the teeth? They are still there! Select the ‘Smudge’ tool and carefully push the white of the two adjoining teeth towards each other. By working slowly from both sites, you can nearly close the gap between the two teeth, but don’t make it disappear completely, that would look again unnatural.
After you have done this, select the dodge tool with a hardness of around 80% and a very small brush size and carefully lighten the gaps between the teeth and any other bits you want to brighten up additionally. Work at 300 to 400% magnification, but switch frequently back to overall view, to see how the finished image starts to look like.

You see teeth whitening in Photoshop is easy, just take care to create your quick mask carefully, save it for further use and play with the setting for ‘desaturate yellow’ and ‘dodge’ until you get a result that is both flattering for you model and natural looking!