Step 1: To begin, click on the Makeover icon on the Paint Shop Pro side toolbar.

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Step 2: Select the Toothbrush from the Makeover toolbar that should now be present under Paint Shop Pro’s main toolbar.

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Step 3: Adjust the Strength of the Toothbrush tool on the Makeover toolbar. A higher setting will make the teeth appear whiter, but that whiteness might bleed into the gums if the value is too high. Also, you want to make sure that that whitening looks natural and not like someone painted the subject’s teeth with typewriter correction fluid.

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I’ve found that a Strength of around 30 usually works perfect for most cases. You can always experiment here with different values and use the Undo button if the setting isn’t right and you want to try again.
Step 4: Move the mouse pointer to any part of the digital photograph containing the teeth of the subject. Click once to apply.

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You don’t have to click on each individual tooth. One click over the area should modify the entire row of teeth. However, if both the top and bottom rows of teeth are showing, you may have to click once on the top row and once on the bottom, depending on the gap between the rows.