My teenage cavities stopped after 1) eating less sugar, and 2) switching to a non-fluoride toothpaste. Now that I'm in my 30s, I have had no cavity issues thus far, but I do have a lot of chipped teeth. I should try fluoride toothpaste again, in order to see 1) if it was the lack of sugar that reduced my cavities, and 2) potentially strengthen my teeth.