What is the Best Recommended Product for Using Trays for Teeth Whitening?

This is a question that I'm asked all the time, but for take home tooth whitening, there really is no one best system. All take home tooth whitening systems have basically similar active ingredients (often carbamide peroxide) with the differences being flavorings, thickeners, etc. As far as trays go, you want ones custom made for you by your dentist, not generic ones you can get at a drug store. With higher concentrations of the active ingredient there does seem to be more sensitivity, this is the main side effect of whitening.

The two most common types of bleaching chemicals available from dentists are hydrogen peroxide and carbamide peroxide.  Hydrogen peroxide is stronger than carbamide peroxide.  These differences in percentages of bleach causes some confusion.  When carbamide peroxide is used, it dissociates (breaks down) to hydrogen peroxide.  The ratio of carbamide peroxide to hydrogen peroxide is roughly 3:1.  So, 30% carbamide is about equal to 10% hydrogen peroxide.  Hydrogen peroxide tends to release its whitening power faster (w/in 30-60 min) than carbamide peroxide, so when using products with hydrogen peroxide, they typically have shorter wear times. They both are effective agents for whitening teeth. 

The Best tooth whitening is the one that works for you.  Modern Dentistry allows Dentists many ways to whiten teeth.  The differences include: speed, cost, comfort, fit, design, taste...  Your Dentist should be familiar with various systems and depending on your goals, should be able to find the right fit for you.  I would choose a professional Dentist prescribed system due to fit/safety/hygiene concerns, but other than that make sure your Dentist is aware of different options and chooses the bleaching system that works for you.  Good Luck.