The Tooth Fairy
Origins of the Tooth Fairy
The origins of what we now think of as the Tooth Fairy can be traced to ancient beliefs in Europe and falls in the realm of "Elves" or "Brownie (elf)" who will often perform useful tasks or exchange valuable treasures for things humans view as mundane or useless. The Vikings had their own ritual called "tooth fee" whereby a small gift was given to a child when its first tooth appeared.
In many European countries the Tooth Fairy was depicted as a mouse. In Spanish-speaking countries the mouse was called Ratoncito Pérez, and in Italy the mouse was called topino (little mouse). Why the figure associated with children's teeth was a mouse is probably because the teeth of mouse (and other rodents) go on growing for its whole life. In some Asian countries, such as Japan and Korea, there exists a similar link between mice and children's teeth. When a tooth falls out of a child, usually he or she should throw it by himself/herself, to the roof when it came from lower jaw or to the space beneath the floor when it came from upper jaw, shouting "please replace it with the tooth of mouse."
So how did mouse metamorphise to fairy?
The belief in magical fairies probably has is strongest association with either Britain or Ireland. Fairy folklore was an ancient belief and applied to many aspects of life. So we had the belief in fairies and the belief in children's teeth and mice. But how did the two cross. There's a tradition from 18th century France of a "tooth mouse," likely based on a fairy tale, La Bonne Petite Souris, in which a fairy changes into a mouse (or perhaps the other way around) to help the good queen defeat the evil king. The mouse hides under a pillow to taunt the king, and punishes him by knocking out all his teeth. Perhaps this was the origin of the tooth fairy, but no one knows for sure.
The tooth fairy as we now know her didn't make an appearance until the early 1900s, as a generalized "good fairy" with a professional specialization. The child loses a baby tooth, which is put under the pillow at night, and the tooth fairy exchanges it for a present, usually money but sometimes candy. Exchanges of this sort are common in many rites of passage (like an exchange of rings at a wedding, say).
The tooth fairy grew slowly in popularity over the next few decades. The Tooth Fairy, a three-act playlet for children by Esther Watkins Arnold, was published in 1927. Lee Rogow's story "The Tooth Fairy" appeared in 1949 and seems to be the first children's story written about the tooth fairy. She became widely popular from the 1950s onward, with a veritable eruption of children's books, cartoons, jokes, etc., including more focus on children's dental hygiene. Parents cheerfully bought into the idea and the tooth fairy became part of family life. The 1980s saw the commercialization and merchandising of the tooth fairy, with special pillows, dolls, banks, etc.
The Tooth Fairy does not have a strong background such as Santa Claus; there's no sense of where she lives, or why she collects children's teeth, or what exactly she looks like. She's very ephemeral. Perhaps this befits her, as a child's teething and loss of milk teeth are also a passing phase of a child's life. But her charm and magic, though short lived, is something remembered by children, as is the charm and magic of the appearance of a child's first tooth and that loss of that tooth remembered by its parents.