An analogy we like is: a cat (which is your immune system) is laying outside of a mouse hole (which is your tooth’s dentinal tubule) wanting the mouse (bacteria, parasite, infection) hiding inside. Except the cat cannot get the mouse to eat it because it’s too big to fit inside the mouse hole, therefore unable to reach the mouse.
The same thing is happing with root canaled teeth. Unfortunately, when the nerve and pulp of the tooth is removed, the immune system is no longer able to reach the infection that persists in the dentinal tubules of the tooth.
This means the infection that caused you to need a root canal in the first place will still be present even after having the procedure done. The worst part is the infection still has access to your lymphatic system, which we know runs throughout your whole body. i.e.) The infection that started in your tooth can still go EVERYWHERE.
Because of this root canal treated teeth are still breading grounds for very harmful anaerobic bacteria and parasites along with their toxins. Often times the toxins from the bacteria or parasites are more harmful than the infection itself. That means every time you chew or grind your teeth those bacteria, parasites and their toxins move from your tooth into your lymphatic tissues. From there they go into your blood stream where they now can literally can go anywhere.