First baby's tooth have symbolic value in many world cultures.

Let's start with Japan. Japanese people throw a lower baby tooth up onto the roof. On the other side an upper tooth is being thrown under the "en-no-shita" which is the area below the floor of a traditional Japanese house. It is done for the upper tooth to grow healthy downwards and the lower tooth upwards.

Almost the same tradition exists in Korea while in Vietnman both upper and lower teeth are thrown on the house. In Turkmenistan a baby tooth is usually buried in the ground or in the footprints of a horse.

The Vikings believed that baby teeth help them in their battles so they have been putting them in their necklaces and other jewelry. There is an old English tradition by which the baby tooth should be dropped into fire.

In Hungary people used to put the baby tooth into a bottle of water. That way the tooth melted in about two years.

Baby tooth is put under baby's pillow in many parts of the world like for example the USA, France, Turkey, Slovenia, Spain and many Latin American countries. In the USA it is believed that a fairy comes to get it. In France, Spain, Mexico and Slovenia it is the mouse who arrives. Depending on the country baby tooth is replaced by money or some present.

French people even have a folk tale about the little mouse. It's called „La Bonne Petite Souris“. It is a story of a mouse that helps a good Queen to defeat an evil King. The mouse changes into a fairy. He then hides under King's pillow tormenting him and knocking out all of his teeth.

In Spain and Latin America, the mouse is called „Ratoncito Perez“ or the „little mouse Perez“ This character was created around 1894 by the priest Luis Coloma. He wrote the story for the 8 years old future Spanish king Alfonso XIII to somehow comfort him as one of his teeth had fallen out.

In Mongolia a baby tooth is given to a young dog. The dog is treated like some sort of a guardian angel there. The tooth is mixed with the food given to a dog. It is believed that when the guardian angel eats the tooth baby will get new strong tooth.

In Chile and Costa Rica mothers make a charm out of their child's baby tooth. The charm is then given back to the children.

In Nigeria mother, father or anyone else who first notice baby's tooth should give some present to a baby. Usually it is a cow, sheep, goat or hen. Such presents are symbols of reproduction and posterity.

In Benin boys hold their tooth and 8 small stones in their hand. Girls hold 6 stones. The child then shouts his or her name and says "I want my tooth back". The child runs away and other children present there bury the tooth in ground. It is believed that if a lizard sees the tooth, a new one will not grow. So, it is very important to keep the tooth hidden.

Finally, let's return to the Middle Ages. Parents used to ground their baby's teeth into powder and eat it. It supposed to protect their children from witches. It sounds disgusting, I know.