Fluoride varnish or remineralizing pastes can be used after whitening to reinforce enamel

https://milowbea115.theburnward.com/the-white-diet-plan-what-to-drink-and-eat-after-your-treatment

Fluoride varnish or remineralizing pastes can be used after whitening to strengthen enamel and minimize sensitivity while preserving your brighter smile.