Why are dental hygiene standards so much higher in America than in Britain?

Americans seem to care much more about dental hygiene than the British do. Everyone I know goes to the dentist regularly, has had orthodontic braces at some point, and generally take care of their teeth. Are the stereotypes about "British teeth" true or is this some sort of myth perpetuated by the American media? *One of the most famous episodes of "The Simpsons" was the one where Lisa goes to the orthodontist and he scares her with the "Big Book of British Teeth"!
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This is a very old stereotype... it's like saying all Americans are fat, which in truth they are not. Similar to what you said everyone I know goes the dentist regularly, almost every teenager that requires braces and retainers get them for free. Dental hygiene is much better than it used to be and more people have the option to have things like braces nowadays.
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