To be fair though, your average trailer dweller probably cleans his teeth on a daily basis. Unfortunately, he uses the oily rag found under the bonnet of his pick-up truck.
American dentists would ineed know about Americans' teeth, but I doubt very much that they would know much of anything about the state of the average Brit's dental habits or teeth.
Similarly, I doubt that you know much more about the folkways of Appalacian whites than you know about Masai tribesman.
If you were to go asking those good ol' boys about how they live they'd hear your Brit accent, call you a sissy-boy foreigner and give you the bum's rush out of the honkeytonk.
By the what do you know what those rednecks woud call a Brit's teeth?
Answer… organ grinders.