Laser Teeth Whitening vs. Bleaching

Dr. Strait's answer is spot on; however, I will add that Dr. Christiansen concluded that the best way to whiten teeth is with a combination of in-office "power bleach" with take home bleaching trays.  

No.  Tray bleaching will work better and cost less.  Plus you can keep the trays to touch up relatively inexpensively in the future, if you want.

Additionally, the only time I ever hear about a 'permanent' or long-term tooth sensitivity caused by whitening is from the 'laser' or light activated type of whitening procedure.

Interestingly,  most dentist that offer 'laser' whitenings aren't actually using a laser.  Rather they are using a blue-light.   Zoom and Bright-smile are both blue lights.  If anyone is getting one of these procedures done, and the dentist says its a laser (or a UV light light for that matter), my recommendation is to immediately leave because that dentist doesn't know what they are doing.

I always tell my patients, "If you're getting married or have a job interview tomorrow, or if you don't want to have to deal with whitening trays, laser whitening is great.  Otherwise, save your money and do the trays."  The trays are in fact much more predictable in my experience.  In fact, we provide trays to our Zoom whitening patients so they can go further if they want.