Why the perfect smile isn't so perfect

Grin & Bare It

The most famous pictures of Lauren Bacall show her casting her classic sultry gaze—with her mouth notably closed. In an interview with People, she said, "I always thought I had crooked eyebrows and crooked teeth. That's why I never understood why people called me a beauty."

Still, unlike other stars of the '40s and '50s, Bacall stuck with her own teeth, rather than opting for temporary porcelain veneers that delivered a megawatt Hollywood smile.

Just Her Size

With her wide-set eyes and delicate features, Jackie Kennedy Onassis' smallish teeth suited her face. (Could you imagine Jackie with a set of big white chompers?)

According to Bakeman, true masters of aesthetic dentistry don't rely on a one-size-fits-all smile. Instead, they "take into consideration other criteria that work to create harmony in the face, such as the arrangement of the teeth, the arch form, where the teeth are positioned within the framework of the lips, the size of the lips, and the relationship to other facial structures."

London Calling

The Brits may be mocked for their less-than-straight teeth (think Austin Powers), but English actress and singer Jane Birkin became a style and beauty icon, imperfect ivories be damned. "Americans have the idea that uniformity is equivalent to looking good. The British character is more free-spirited, more radical," said British dental professor Liz Kay in a BBC News article on American versus British teeth.

Loving It

Except for a single front tooth angling inward, Ali MacGraw's face is pretty much flawless. At the start of her career, one Hollywood director urged her to have the tooth fixed, but MacGraw apparently laughed off the suggestion. Nearly 42 years after she starred in Love Story, MacGraw's imperfection has become part of her signature natural and carefree look.

Chipping In

The former face of Lancôme (for 14 years!), Isabella Rossellini had this to say about her teeth in a 1985 interview with Life: "I think teeth have their own equilibrium—is that the word? I have perfect teeth, no cavities: just this big chip."

Looking Sharp

The fang-toothed grin on model Kate Moss has a youthful appeal that's made it popular in parts of Japan, where women are using fake teeth to effect the same look. (Read more about it here.)

What Moss does have going for her smile is symmetry between the two front teeth, something Bakeman says is "of the utmost importance." She adds that as you move away from the front teeth "subtle differences in symmetry are appealing and natural."

C'est la Vie

The gap between French actress Vanessa Paradis' front teeth makes Lauren Hutton's own space look small. While we could rattle off a quick list of gap-happy beauties, Irwin Smigel, DDS, the so-called father of aesthetic dentistry, shares his assessment of the trend: "If someone is really beautiful, then the space makes them look a lot more natural," he says. "But if the average person makes the space, then people will stare at the space."

Model Behavior

There's a spate of new models with gaping gaps in the fashion industry, where looking different has become de rigueur. As almost every model's "before I was discovered" story goes, current "it" girl Lindsey Wixson was awkward and made fun of for her teeth in middle school.