Lip Anatomy


When you look at someone you see their face. Maybe not the first thing noticed but noticed are the lips. So I pose a trivia question: what is cupid’s bow? (Answer to follow)


The upper and lower lip are anatomically called labium superius oris and labium inferius oris, which are the Latin terms used by professionals. The right and left corners of the mouth are known as the commissure.    The reddish area of the lips is know the vermilion zone, and where it meets the facial skin is known as the vermilion border (vermilion meets bright red or scarlet). The surface of the lip has only 3-5 layers of epithelium compared to the face which has up to 16 layers.

Lips do not have hair or sweat glands. They are more prone to drying out and chapping. The commissure (corner of the mouth)  can not only dry out but stay moist inviting fungus to grow, usually candidiasis. (Treated with an anti-fungal like athlete’s foot cream).

Lip protection is important. If you have chapped lips, a lip balm can help. If you’re out in the sun, you definitely want protection from the sun or you may be much more susceptible to lip cancer when you get older. Herpes labialis in the form of a cold sore is a quite common virus. Be careful of spreading this to others, even something as casual as kissing your 3 year old nephew. There are different anti-viral drugs that can help to speed up the episode from 10 days or so down to just a few days.

As a dentist we see lips before we see the teeth when doing an examination. We can help with that, but for anything that is more troubling like a suspected carcinoma, the dermatologist the specialist to deal with this. With the population getting older it is an increasingly more common condition.

The answer to the trivia question, as quoted from Wikipedia:

“The Cupid’s bow or tubercle is a facial feature where the double curve of a human upper lip is said to resemble the bow of Cupid, the Roman god of erotic love. The peaks of the bow coincide with the philtral columns giving a prominent bow appearance to the lip. It is seen in fetal hydantoin syndrome.

The phrase is common in literature, often used related to speech, and therefore the mouth, as inVenus and Adonis:

For pity now she can no more detain him; (577)

The poor fool prays her that he may depart:

She is resolv’d no longer to restrain him,

Bids him farewell, and look well to her heart, (580)

The which, by Cupid’s bow she doth protest.”

Extract From Shakespeare”