Cleft lip and cleft palate, which can also occur together as cleft lip and palate, are variations of a type of clefting congenital deformity caused by abnormal facial development during gestation. A cleft is a fissure or opening—a gap. It is the non-fusion of the body's natural structures that form before birth.
Clefts can also affect other parts of the face, such as the eyes, ears, nose, cheeks, and forehead.
If the cleft does not affect the palate structure of the mouth it is referred to as cleft lip. Cleft lip is formed in the top of the lip as either a small gap or an indentation in the lip (partial or incomplete cleft) or it continues into the nose (complete cleft). Lip cleft can occur as a one sided (unilateral) or two sided (bilateral).
Cleft palate is due to the failure of fusion of the maxillary and medial nasal processes (formation of the primary palate). It is a condition in which the two plates of the skull that form the hard palate (roof of the mouth) are not completely joined. Below, is an example of cleft lip and palate.
Cleft lip and palate is very treatable; however, the kind of treatment depends on the type and severity of the cleft.
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