Scientific thinking on root canal treatment?

Have you googled for other sources of info? I did a quick search on Pub Med but didn't find anything. (maybe you can find something I missed?) Dr. Weil's website explains the theory but then says he'd choose an RTC over an extraction. FWIW, previously I had googled the originator of the idea that RTC cause other systemic problems. (he published his book in the 1930s or so and it was followed for awhile and then discredited). I couldn't find data to prove the theory to be correct, but maybe someone else can?

Yeah, it's tricky. We don't know what causes BC and a lot of theories may sound plausible but we don't have data. (and sometimes theories sound good but don't hold up in clinical trials). In some cases, it's easy to take the conservative approach. i.e. I think the chemical BPA may be a contributor, so it's easy for me to avoid canned foods and other sources. My sense is that there aren't any terrific alternatives to a RTC (and sometimes the Tx seems ok today and we learn more later. i.e. people removed their mercury fillings and replaced them with the "white" kind, only to find out later that those had questionable chemicals in them). Anyway my understanding is that, yes, sometimes there can be an infection outside the tooth at the tip (apex) but the DDS can detect that, either visually or with a digital Xray. (I avoid Xrays if I can, but if you have problems in the future, this is one way to get more info. FWIW digital xrays are supposed to have much less radiation than the old kind). Now that I'm middle aged,  more and more of my friends are getting RTCs. The risk of dental problems and cancer goes up as we age, but that doesn't mean there's a cause and effect.  I know that 1:8 women will be Dx'd with BC, but I've never seen data for the prevalence of RTCs in the general population. Also, I've never seen data that shows that cancer patients have a higher rate of RTCs than the general population. But everyone has to decide what makes sense to them and what risks and trade-offs they are willing to make.