Philtrum

Philtrum

The Philtrum is a vertical groove in the middle area of the upper lip, common to many mammals, extending in humans from the nasal septum to the tubercle of the upper lip. Together with a glandular rhinarium and slit-like nostrils, it is believed to constitute the primitive condition for mammals in general.

Anatomy

The philtrum is a residual reminder of the time in the womb where the two sides of the face meet in the middle to form the facial features. This meeting point creates the groove, which is a vertical indentation in the middle area of the upper lip that extends from the nose to the upper lip. The philtrum is also referred to as the infranasal depression.

Function

While the human philtrum is a vestigial structure without function, it does carry a strong aesthetic importance. In many mammals, the philtrum carries moisture from the mouth to the rhinarium or nose pad through capillary action to keep the nose wet. A wet nose is a significant factor in scenting ability, and the philtrum helps to keep the nose wet by drawing moisture up from the mouth.

In other animals

In most mammals, the philtrum is a narrow groove that may carry moisture from the mouth to the rhinarium or nose pad through capillary action, to keep the nose wet. A wet nose is essential for determining the direction of the air current containing the smell.

In medicine

In medicine, the length of the philtrum is measured during physical examination. A long philtrum is associated with Fetal alcohol syndrome and some genetic disorders like Smith-Lemli-Opitz syndrome. A short philtrum signifies early maturity, often associated with Down syndrome.

Cultural views

In some cultures, the philtrum is viewed as a sign of beauty, and in others, it is associated with eroticism. In ancient Rome, the word "philtrum" was used to describe a love potion.

See also

• Cupid's bow
• Intermaxillary segment
• Mammalian philtrum

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  Philtrum of a baby
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  Philtrum of a dog
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  Philtrum of a Tahitian man