Do my teeth have to be dry before doing the treatment? June 17, 2021 13:23 Updated Yes, we recommend drying your teeth before applying the pen for a better usage experience Related articles Do you need to brush your teeth before eating in the morning after using the pen? Am I allowed to eat or drink after application? Can I use this with a mouth guard or Invisalign type of braces? What is the whitening ingredient in the pen? How does it work? Is there an interval in between treatment cycles? How much time should I wait to go through the whitening cycle again? Comments 0 comments Article is closed for comments.