Cleft lip and palate

Definition:

A facial birth defect (congenital abnormality). A cleft lip affects the upper lip, ranging from a notch to a complete fissure extending into the nose. A cleft palate affects the roof of the mouth, with a groove that may extend through the dental arch (hard palate). These abnormalities may occur separately or together.

Causes, incidence, and risk factors:

Cleft lip and palate are facial malformations that may occur separately or together. They may also occur in association with other syndromes or birth defects. The separation of the lip can vary from a small notch to a complete separation extending into the nose. The cause of these malformations may be mutant genes or teratogens (an agent that causes abnormalities in a developing fetus such as certain viruses or chemicals). As well as being disfiguring, these abnormalities can cause feeding difficulties and problems with speech development. Risk factors are a family history of cleft lip or palate and presence of another birth defect. The incidence of cleft lip and palate varies with different races; approximately 1 out of 1,000 Caucasians are affected. The incidence of cleft palate alone is 1 out of 2,500 people.