A Touch Up Session is intended as a refresher if after a certain period of time you think your teeth are starting to recede after your previous whitening session

How long your teeth stay white depends on how you care for them and what you eat and drink. Because eating red pasta sauce, for example, can cause discoloration, just like drinking coffee or cola and don't forget smoking, this all causes discoloration of the teeth.

Touch Up Session is a teeth whitening treatment and is intended as a "repeat" treatment if the white tint of your teeth starts to fade over time.