"Still, the infection's never come back though I rarely pull with oregano, and have many weeks when (I'm embarrased to say here) I don't pull at all. So it wouldn't make any sense that oil pulling (at least with my irregular practice) is keeping some kind of persistance infection at bay. Though if it could that should be reason enough for the world of dentistry to embrace it with open arms."
Same thing happens when you give Antibiotics to someone with an infected tooth. The infection is cleared from the bone, but remains in the tooth. It always returns either weeks or 2-3 months later. I have seen patient after patient come for emergency care, are given Antibiotics , disappear, and come back months later because the same tooth is causing the infection to return.
"But am I understanding you corretly to say that there's no blood flow in our teeth? Or just when there's some kind of infection and swelling?"
No, in a normal healthy tooth, there is normal blood flow. There are no lymph vessels in a tooth though. When you get an infected tooth, the bacteria buildup, along with the body's natural response to flood the area with blood and immune cells, combined with the confined nature of a tooth will increase the pressure inside the tooth to the point that blood flow into the tooth will stop. This prevents the normal infection fighting and healing process that takes place anywhere else in the body, thereby killing the tissue inside.