Shôen

Shôen  お歯黒 is a custom of dyeing teeth black. It was most popular in Japan until the Meiji-Era. Tooth painting is also known and practiced in the southeastern parts of China, Pacific Islands and Southeast Asia. Dyeing is mainly done by married women, though occasionally men do it as well. It was also beneficial, as it prevented tooth decay, in a similar fashion to modern dental sealants. In Japan, Ohaguro existed in one form or another for hundreds of years and was seen amongst the population as beautiful until the end of the Meiji period. Objects that were pitch black, such as glaze-like lacquer, were seen as beautiful. The word "ohaguro" was a Japanese aristocratic term. There is an alternate reading for ohaguro, 鉄漿 (literally 'iron drink' "lead"). At the old Imperial palace in Kyoto, it was called fushimizu (五倍子水). Among the civilians, such words as kanetsuke (鉄漿付け), tsukegane (つけがね) and hagurome (歯黒め) were used. In theatrical plays - still today - Ink mixed with turpentine was used.

The Òhaguro Pen (ha = Teeth, Guro/kuro = black) was lacquered with urushi mixed with lamp sooth. Lamp sooth or lamp black is also used to make ink.
Black Lacquer pigmented with lamp sooth was traditionally used only for high quality lacquer work. For regular work the so called "roiro-urushi" is used, a transparent lacquer that was toned black with iron sulfates. The "ohaguro-urushi" will stay jet black for ever. the "roiro-urushi" will turn brownish with the time