The philtrum refers to the groove that most humans have above the upper lip. The philtrum is also referred to as the infranasal depression. This portion of the human face is formed during embryonic development. While seemingly useless, the philtrum allows for extensive facial expressions, and it also allows humans to speak clearly and precisely.
When this portion of the face is not formed during development, a cleft lip may develop instead. Babies who are born without a groove above the upper lip may be victims of fetal alcohol syndrome. In most cases, the length and depth of this facial groove is often determined by genetics. Some people have short philtrums, which also can be a genetic defect.
Causes of a shortened philtrum include Cohen disease, chromosome 18q deletion syndrome, DiGeorge syndrome, and Oral-facial-digital syndrome. Babies who are not born with a groove above the upper lip may have Williams Syndrome. This syndrome occurs when certain genes are missing. Often, parents that have Williams syndrome can pass this defect onto their children, though this is not always the case.
Symptoms of Williams syndrome include delayed speech, trouble concentrating, learning disorders, strange personality traits, and a sunken chest. Often, this syndrome is not noticed or recognized until a child is much older. Once symptoms of Williams Syndrome have been found, medical attention should be sought immediately.
Philtrums are similar to fingerprints in many ways. All philtrums tend to be different from one person to the next, though this small grooved area is essential for proper speech and mouth development. Children that are born with a cleft lip, or hare lip, should be seen by speech therapists right away in order to avoid speech difficulties.
The word philtrum comes from the Ancient Greek word philtron, which means to love or to kiss. According to Ancient Greek mythology, the philtrum is one of the most sensual parts of the body. Thus, many stories related to this portion of the face are woven into Greek mythology. In addition, this small indentation is largely mentioned in the Jewish Talmud.
Other traditions include stories of angels hushing babies inside of the womb by placing one finger above a child's mouth. Within a number of religions, it is believed that babies hold all the secrets of Heaven prior to being born. Thus, angels must quiet a child by erasing such memories before a child can be born. These folktales include the hypothesis that an angel's touch upon a baby creates a small indentation.