听说过涂黑牙齿是日本早期妇女的fashion，还真不知原因。刚查了下：

Why did the Vietnamese, Japanese, and Chinese blacken their teeth for centuries? How did the custom form?

This is best answer which is chosen by Asker from Yahoo! Answers: During the Heian period in Japan, there was a court lady who was the most beautiful woman ever seen. She was complimented on her beauty, but her modesty was as great as her beauty, and she didn't wish to seem proud or vain. So she blackened her teeth to look uglier.
However, the purity and unselfishness of her act made her a beautiful person through and through, so everyone still admired her. Later other women tried to imitate and emulate this modesty by also blackening their teeth, and it became the fashion.

Heian period 就是平安时代，八世纪末到十二世纪。

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• 感人。有点象Lady Godiva 的故事。谢谢浮生。 -打字难- ♀ (0 bytes) () 12/16/2006 postreply 21:04:45