Ohaguro (お歯黒) was the Japanese custom of blackening your teeth. It was also known as Kane (鉄漿).
Up until the 19th century it was thought to enhance sexual appeal as well as help to maintain healthy teeth.
Until the 12th centruy was see it used as a sign for a girl coming of age, and during this century the practise spread to the nobility and Samurai.
By the 18th century it again became confined to all women, but later only married women until the practice died.1
1. Kodansha. (1993) ”Japan: An Illustrated Encyclopedia”. Tokyo: Kodansha Ltd.
2. Yoda, H. and Alt, M. (2016) “Japandemonium: Illustrated: The Yokai Encyclopaedia of Toriyama Sekien.”. New York: over Publications, Inc.
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