A cleft lip is a gap in the upper lip.
It is one of the most common facial anomaliestreated by plastic surgeons.
There are several different types of cleft lip.
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Cleft lip has historically been referred to as “hare lip.”
This moniker came about because of the natural split that is present in the upper lip of rabbits/hares.
The term hare lip is no longer used in the medical community as it is viewed as derogatory.
Verywell / Millicent Odunze, M.D., M.P.H.
Cleft lip andcleft palateare different.
Not all individuals with cleft lips have a cleft palate.
And not all individuals with a cleft palate have a cleft lip.
Verywell / Millicent Odunze, M.D., M.P.H.
It is possible for an individual to have both a cleft lip and a cleft palate.
In this article, you will learn the names of the parts of a normal lip.
You will also learn about the different types of cleft lips unilateral versus bilateral, complete versus incomplete.
Verywell / Millicent Odunze, M.D., M.P.H.
Unilateral means the lip has a cleft on one side.Bilateralmeans there is a cleft on both sides.
Complete indicates that the cleft extends from the lip all the way into the nose.
Incomplete involves the lip but spares the nose.
Verywell / Millicent Odunze, M.D., M.P.H.
Causes of Cleft Lip
The cause of cleft lip is not well understood.
During fetal development, nasal and lip elements do not come together properly.
Researchers believe some cleft lips may have genetic causes.
Verywell / Millicent Odunze, M.D., M.P.H.
Others could happen because of something in the environment or a medication taken during pregnancy.
For example, people who smoke during pregnancy are more likely to have a baby with a cleft lip.
Normal anatomy consists of an upper and lower lip.
Verywell / Millicent Odunze, M.D., M.P.H.
Cleft lip affects the upper lip.
The upper lip has several components.
Microform Cleft Lip
Verywell / Millicent Odunze, M.D., M.P.H.
A microform cleft lip does not have the obvious cleft appearance of the other clefts.
It may simply appear as a vertical scar from the lip to the nose.
There may be a notch in the vermillion border and the nose may be affected.
While a microform cleft may not be obvious, there may still be a problem with functionality.
There is some disruption of the continuity of the orbicularis oris muscle.
This may cause eating and drinking issues as well as speech issues.
The nose is usually normal with a microform cleft deformity.
The actor, Joaquin Phoenix, has a microform cleft lip.
It appears as if he has a surgical scar from repair of a cleft lip.
In actuality, that is his natural appearance.
Unilateral Complete Cleft Lip
A unilateral cleft lip only affects one side of the upper lip.
These are the most common types of cleft lip.
Two-thirds of theCupids bow, one philtral column, and the philtral dimple are preserved on the noncleft/normal side.
The cleft extends all the way from the lip to the nose in a complete cleft lip.
The orbicularis oris muscle is not in continuity in a complete cleft lip.
This disruption creates difficulty speaking, eating and drinking.
The nose is distorted with a cleft lip deformity.
The nostril is widened and the floor of the nostril is missing in a complete cleft lip deformity.
Unilateral Incomplete Cleft Lip
A unilateral cleft lip has clefting of the lip on one side only.
There is a normal philtral column, Cupid’s bow and philtral dimple on the side without a cleft.
What makes it different from a complete cleft lip is that some orbicularis muscle fibers may cross the cleft.
Incomplete cleft lips can take on a variety of appearances.
As with a complete cleft lip deformity, the nose has some distortion.
The distortion is usually to a lesser degree.
The nostril may be widened, but the floor of the nostril is intact.
Additionally, there is a bridge of tissue at the base of the nostril on the cleft side.
This is known as a Simonarts band.
On both sides, the cleft extends from the vermillion to the nostril.
The lack of continuity in the muscle makes clear speech difficult for these individuals.
Feeding can be more difficult.
There is nasal distortion with a bilateral complete cleft lip.
Both alar rims are widened, the nasal sills are missing and the nose takes on a flattened appearance.
Just like with a bilateral complete cleft lip, the philtral columns are affected.
To what degree depends on how far up the cleft extends from the vermillion.
There may be some orbicularis muscle intact.
The nostril sills are intact.
The philtral dimple is intact.
An incomplete cleft lip may be barely imperceptible.
Frequently Asked Questions
Cleft lip can be repaired surgically.
With treatment, most children born with cleft lip have a normal life expectancy.
Children with cleft lip who die in infancy often have other congenital abnormalities.
Centers for Disease Control and Prevention.Cleft lip/cleft palate.
2012;49(4):508-11. doi: 10.1597/10-179
