Teeth Whitening in Photoshop

I have seen questions arise on occasion in Adobe's Photoshop User to User Forum from Photoshop users wanting to know how to use Photoshop to whiten a person's teeth.  There are several approaches, one common technique simply making careful use of the Sponge Tool to desaturate the offending colors.  But, one of my favorite techniques is one which I learned from a Denny Tang tutorial that no longer seems to be on his website.  More complicated than some approaches, making use of a saturation adjustment layer and blending mode changes, it seems to give what I feel is a more natural looking result, and is what I used to create the image below that I gave to my personal dentist.  The tutorial itself is provided in PDF format and may be found here: Teeth Whitening Tutorial by Denny Tang.  Thanks Denny!