Causes of a cleft

In the majority of cases, the cause of a cleft is not clear.

Cleft can be caused by a combination of predisposing factors and external effects in the period between six and twelve weeks after conception.

The causes can be classified into three groups:

A disorder in pregnancy
In normal development exists in everyone initially a bilateral cleft lip, jaw and palate. (See drawing below)
Normally grow the various parts towards each other and merge. Between the sixth and ninth week of pregnancy close the lip and the upper jaw itself. Between the ninth and twelfth week the palate. If this process is not complete or place, there remain gaps exist.

Genetic factors
Genetic factors play a role at the moment of conception. The cleft may for example be caused by a chromosomal abnormality. Usually there except a cleft yet another congenital deformities. Another possibility is that the construction for cleft via one or both of the parents is passed. Cleft is than when one or both parents, and / or one or more family members.
A combination of factors
Most likely, cleft by a combination of genetic factors and external disturbances in the ‘sensitive period’ of the embryonic

There are different types of clefts:

A crack in the lip (cheilo-cleft)
A crack in the lip and jaw (cheilo-gnatho-cleft)
A gap in the lip, jaw and palate (cheilo-gnatho-palato-schisis)
A gap in the palate (palato-schisis)
Variation in manifestations
The variation in appearance is large.

Typically, the gap in the lip not in the center, but like in addition, from the center of the lip to the nostril. A gap may be left or right, but it can also prevent the left and right.

A gap may be complete or incomplete.

A cleft lip can range from a small dent in the lips red (incomplete cleft) to a double slit which extends into the nasal floor (complete cleft).
A cleft palate can range from a crack in the uvula to the almost complete lack of the palate.
A jaw gap can range from an indentation in the jaw to a full duplex gap
Consequences of a cleft

Nutrition, hearing and speech

Except for the appearance cleft may also affect:

the power supply
the speech
the nose
the teeth
The consequences are determined by the shape of cleft that your child has.
The consequences of a lip-en/of jaw gap are limited. A gap in the palate from birth may affect feeding, speech and hearing.


Drawing 1: closure of the cleft lip according to the common method of Millard. Left a left-sided slit, the situation right after surgery.


Drawing 2: closure of the palate. Left the situation before surgery, soft palate and uvula are split. Right the situation during surgery, if possible, the palate in its fully closed.


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