Brushing teeth is cultural behavior - it is counter natural. The natural condition is to lose teeth. Our evolutionary response to that was to grow in wisdom teeth. Now have our dental hygiene habits triggered an evolution toward no wisdom teeth? Or do people who lack wisdom teeth belong to the earlier category of human evolution prior to the development of wisdom teeth?
I don't think we lived long enough to lose many teeth back prehistory. I'm not sure where you're going with this.
susie