I also have a tooth with a big hole (where the filling fell out) for a couple years now. On the two occasions it's gotten infected, oil pulling with oregano took care of it nicely.

Personally if I had an open root canal, I'd increase the frequency probably to two times a day - and use a good germ killing oil like coconut or a few drops of oregano oil (diluted with something else).

In fact there's no way I'd let them seal back the tooth without lots of oil, water, and Colloidal Silver swishing. Not that I wouldn't trust the dentist to properly clean the canal or anything..;)