alt Hacker NewsThis guy's been downvoted badly but he's right - vitamin k2 make your teeth into "superteeth".
I started K2 about 10 years ago. Next dental checkup (about a year too late) the dental tech said my teeth appeared recently-cleaned. This has continued since then. No cavities, little cleaning required other than regular brushing, flossing and taking k2.
IIRC plaque is mineralized by saliva in the same way as tooth enamel, so something that changes saliva in a way that prevents tartar from forming might be reducing the amount of calcium in your saliva in a way that could potentially ultimately not be good for your teeth.