A recent study put out in the Springer Nature publication found that people who have good teeth have a high population of good bacteria in the mouth.
(Hint - No Toothpaste or Mouthwash Involved)
As it turns out, many common dental products (such as toothpaste and mouthwash) contain toxic ingredients that can destroy the microbiome in the mouth. This explains why teeth can thrive for hundreds of years outside the mouth (in fossils), while in our mouth they get ruined by something so simple as chocolate.