In a country in denial about class divisions, a mangled mouth is the clearest indication of second-class citizenship. Missing or rotting teeth are like a scarlet T, declaring their owner to be trash. Sered and Fernandopulle describe the way that a group of well-meaning Idaho women who volunteered at clinics and early childhood development programs judged "those people" who weren't able to get dental care for themselves or for their children. "These middle-class women," they wrote, "identified bad teeth as a sign of poor parenting, low educational achievement, and slow or faulty intellectual development." When Stu Price, Ed Helms' character in The Hangover, wakes up in Las Vegas and discovers he is missing a front tooth, his horrified response is to declare, "I look like a nerd hillbilly." Every lazy screenwriter knows how to label a character as a menacing half-wit: give him gnarly teeth and a sleeveless T-shirt.

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