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90% Reduction: Scientists Discover Natural Molecule That Eradicates Plaques and Cavities
(scitechdaily.com)
it is the place for high quality scientific content that doesn't necessarily reference a peer-reviewed paper from the last 6 months.
This is basically saying kale is good for you:
https://en.wikipedia.org/wiki/3,3%27-Diindolylmethane
If I'm reading that link correctly, you need to digest the kale to release it, so it's not going to help your teeth. Unless it can also come out via cooking or saliva?