And some dentists are straight up charlatans wanting to line their pockets. When I moved across the bay I left my dentist of 10+ years and went in search of someone closer. I admit to delaying a couple years, but found a place, got cleaned and x-rayed. The dentist told me I had 13 cavities that needed to be tended to. I was pretty shocked; I don't have great teeth, but to have developed that many cavities in such a short time seemed wrong. I went back to my old dentist for a second opinion and he told me that I had 2 genuine cavities at the edges of old fillings, but the rest of it was pretty much nonsense: amalgam fillings that could be replaced with porcelain for appearance but were still perfectly good, and some slight discolorations that were not actually cavities.