Dentist warns why you should never use mouthwash after brushing teeth

Is there any evidence that the specific type of fluoride salts added orally via the toothpaste actually provide anything beneficial? Asking because I have seen some biologists get into arguments about this very topic specific to the type of fluoride solutions. [1a][1b] Just curious really. Fluoride has some interesting properties. [2] Apparently some cities have blocked water companies from adding it to the water supply. [3][4] 74 cities. Some foods naturally contain fluoride. [5]

[1a] - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6195894/

[1b] - https://www.youtube.com/watch?v=t1oPcYDFPRU [video]

[2] - https://en.wikipedia.org/wiki/Sodium_fluoride

[3] - https://www.oregonlive.com/portland/2013/05/portland_fluorid...

[4] - https://www.nbcnews.com/news/us-news/science-says-fluoride-w...

[5] - https://strongsmilesdental.com/blog/foods-naturally-contain-...

I have had two entirely separate dentists tell me to avoid mouthwash, except as something to cleanse the mouth with quickly after a coke or to freshen my breath.

The first dentist suggested that it may make plaque worse, but they never gave me an explanation.

5 years later a different dentist told me to avoid mouthwash and instead to 'mouthwash' with the fluoride foam from brushing my teeth, before spitting that foam out and then not rinsing with water.

This makes no sense. According to this dentist on TikTok mouthwash is bad to use after brushing because it has a lower concentration of fluoride. But a few lines down in the article:

> "Rinsing with water is better than rinsing with mouthwash, just brush then spit out the excess, try not to rinse."

All of the advice in this article makes no sense to me.

> "Now if you were to go and brush your teeth [after eating], what’s happening is that you’re brushing the acid into your tooth," the health professional insisted. "And this causes tooth erosion. So to get your teeth out of this critical zone, use mouthwash."