First choose your Magic Wand tool, lasso tool (or any other selection tool) to put a selection around your teeth. To refine your selection, go to Quick Mask mode and use your Paintbrush tool to modify the mask.
Now that you have a refined mask, feather the selection radius by 2 pixels (Select > Feather) to give a nice blended edge. First remove the yellowing (Layer > New Adjustment Layer > Hue/Saturation). Select Ok. When the Hue/Saturation dialog box appears, from the Edit pop-up menu, choose Yellows. Then to remove yellowing, lower the Saturation slider.
There are two ways to brighten the teeth. Choose anyone from following.
- First Method -> Now from the Edit pop-up menu, choose Master and drag the Lightness slider to the right to brighten the teeth.
- Second Method -> Select (Layer > New Adjustment Layer > Levels), and move the middle slider to the left a bit. Different amounts of whitening are called for in every image, so use your own judgment and experiment until it looks right to you.
In the end I would like to say that I tried to make the teeth’s better and not make them unrealistic. In fact, the little imperfections part of a real-live person. As you know suggestion and comments are always welcome on my email address: firstname.lastname@example.org