Paul McDonald Explains Pearly Whites: "I Was Going to Be a Pediatric Dentist"

Paul McDonald has made a name for himself on American Idol not only for his musical talent, but also for his pearly whites! So what's his secret?

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"I brush 'em once or twice a day, I try to keep them decent," Paul explained to MTV News Thursday night.

And Paul even decided to promote the toothpaste he uses (since high school) in hopes he'll get a deal out of the company — Crest Advanced Vivid White.

Hey, if he doesn't get named America's idol maybe he can do commercials!

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"For some reason it keeps them lookin' all right, you know?" Paul added. "And I was going to be a dentist beforehand, before all this rock 'n' roll stuff started, so I figured I need to keep my teeth decent."

"I'm being dead serious," he continued. "I went to school for biomedical sciences and I was going to be a pediatric dentist before the rock 'n' roll singer/songwriter path took off."