What does having a cavity have to do with playing football? Nothing. But if you found cavities in 110 of 111 people who ate a lot of candy and didn't brush their teeth daily you might have an analogy.Ugh, I hate articles like this. CTE and its connection to football is a real and frightening thing, but studies based on self selection are silly and give fodder to deniers. If a self selecting study showed that 110 out of 111 football players who believed they have a cavity turned out to be right, does that prove anything about cavity prevalence in the NFL?
But I get your point.