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Doubt it's one in a billion.
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Of course, any non-citizen in the U.S. (escapee from the local pen or whatever LOL) can get a filling at the dentist's for about $75-100. Your wife's was a lot less? Or she got a root canal for $10 or something? :- )
A simple doctor's office visit in the U.S., no insurance, is about $50-100 and if you're hurting, a lot of doc's will give you a break.
Hospitals in the U.S. have to care for dire circumstances, no cost, for those who can't pay. A guy is wheeled into an ER unconscious from a car wreck, they're going to treat him, right?
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Not trying to minimize. Just trying to put it in scale.