Okay maybe I should be a little more specific, i'm debating in regards of the oil "pulling impurities" out of your blood. I just don't see how they would work, unless you were pulling and sucking out blood.
When you chew gum, do you suck and push your saliva through your teeth? i'm guessing not, unless you chew your gum a different way.
I'm not encouraging the use of mouth wash, hell I don't even use it, it contains alcohols that make my mouth all dry. I'm just trying to find an explanation for why OPing makes your teeth look so good, rather it from pulling impurities out of your blood stream.