I know what you mean about having a lifetime of dentist assault on your mouth. We had an eager beaver family dentist who decided that my mouth had to bankroll his practice. He filled every tooth in my mouth with mercury by the time I was 18. That done he then convinced my parents that most of my teeth actually needed double fillings!
So I'm hardly an example of pristine dental health. But you'd be amazed at what regular oil pulling will do for your oral health no matter what the situation. In fact if you have tons of root canal and other cavitations, it's a must to keep bacteria counts down to minimize heart disease etc. Not to mention making sure it doesn't get reinfected and another root canal needed in the same spot. Most dentists will tell you a root canal can be expected to last only 10-15 years.