Should I use 22% or 35% bleaching gel?
Both 22% and 35% carbamide peroxide are effective and gentle for your teeth. However the 35% mixture is the most effective and you will obtain the desired result more quickly using less bleaching treatments. 35% carbamide peroxide is intended for normal mouths that are not prone to irritation. If you have a sore and sensitive mouth, problems with painful gums or particular problems with sensitive teeth, we recommend that you use the 22% mixture.