Cleft Lip and Palate Causes and Risk Factors: Inherited Factors (genes) Interacting with Certain Environmental Factors

Lip and Palate - Causes and Risk Factors

Clefts arise when the lip and mouth do not fuse properly in the second and third months of pregnancy. While many possible causes of clefts are being investigated, no single cause has been identified. The majority of clefts may be due to a combination of inherited factors (genes) interacting with certain environmental factors. Clefts run in families to some extent. If one parent or child in a family has a cleft, the chances of a subsequent child being born with a cleft increases from the usual 1 in 500 to approximately 1 in 20. Parents in such situations should meet with a geneticist to find out the approximate risk of having another baby with a cleft.

Children with cleft lip and palate have special concerns related to their teeth and jaws. Most have special dental problems. A cleft may involve the alveolar ridge (bone with teeth growing inside). Since the area of the cleft has no bone, there may be one or more teeth missing, the teeth may be defective in their shape or surface (enamel), or they may erupt into an abnormal position (rotated, tilted etc.) There may even be extra teeth. The teeth most commonly affected are the upper incisors and canines on the side of the cleft.