Years ago I got a root canal by an over-zealous dentist...it was an awful experience for me, especially when I looked back on it and thought it was unnecessary.
The tooth that was worked on and capped once again got infected, and I had a visible abscess that scared the living #$*! out of me. BUT...I didn't want to go back to the dentist, so I started researching...
After much perusing, I cut out sugar and most refined foods and added grass-fed cow's butter, cod liver oil, and lots of fermented foods to my daily diet. Abscess completely went away, and I haven't had a cavity since. Also, for toothpaste I use activated charcoal, coconut oil, and bentonite clay with a little peppermint oil every other day and baking soda the rest of the time. I floss and use hydrogen peroxide to rinse. I haven't been to the dentist in 5 years, and my next visit is coming up--I'm willing to bet I don't have any cavities still :)
"Nature is not a place to visit. It is home." --Gary Snyder