There are fluoride gels designed to apply after rinsing that you might consider. E.g., CTX4 [1]. There is an over-the-counter version and a prescription version

There are fluoride gels designed to apply after rinsing that you might consider. E.g., CTX4 [1]. There is an over-the-counter version and a prescription version, with the prescription version having a much higher fluoride level. Many dentists sell the prescription version, often without the formality of a prescription as long as you are a patient of theirs. They are maybe 2 or 3 times as expensive as regular toothpaste, but in my experience a tube lasts way longer than a tube of regular toothpaste. That's because when you are just using them to apply fluoride at the end rather than to clean you don't need very much. Just put a small amount on a toothbrush and rub it over all the teeth. [1] https://www.drugs.com/pro/ctx4-gel-5000.html https://www.drugs.com/pro/ctx4-gel-5000.html