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Key Points
Overall incidence is 1 in 700 births. Marked ethnic and racial variation occurs in cleft lip with or without cleft palate.
Seventy percent of cases are nonsyndromic, 30% are syndromic based on the presence of other anomalies and/or developmental delay.
2D sonographic detection rate of orofacial clefts is on the order of 65% to 73% of cases. 3D sonography allows better visualization of defects in the palate and MRI allows assessment of secondary palate.
If a suspected orofacial cleft is diagnosed, referral should be made to a level II facility. Prenatal karyotype should be considered. There is a high rate of associated anomalies, particularly of the heart and central nervous system.
Fetal treatment has been performed on animals.
Long-term issues include midface hypoplasia, facial appearance, dental abnormalities, speech disorders, and hearing problems.
More than 400 single-gene disorders are associated with cleft lip and palate. A family history should be obtained, and parents should be examined for subtle findings such as bifid uvula and missing teeth.
At birth a thorough physical examination should be performed and a medical geneticist should be consulted. Many infants are treated by a multidisciplinary team that includes emphasis on feeding and adequate nutrition.
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Cleft lip and palate are relatively common facial malformations that occur early in gestation. Although they are distinct anomalies, they frequently occur together (Seeds and Cefalo, 1983). In all cases of orofacial clefting, 60% to 75% involve cleft lip, with or without cleft palate, and 25% to 40% are isolated cleft palate (Figure 23-1). Most cases (80%) are unilateral, occurring twice as commonly on the left side as on the right (Gorlin et al., 1971; Seeds and Cefalo, 1983; Bronshtein et al., 1991). Isolated cleft palate is more frequently associated with other anomalies (Jones, 1988a).
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Orofacial clefts derive from abnormalities in the migration and proliferation of facial mesenchyme, a neural crest cell derivative. Coalescence of facial mesenchyme results in the formation of the primary palate, which creates the initial separation between oral and nasal cavities, eventually creating part of the upper lip and anterior maxilla (Ross and Johnston, 1972). Cleft lip with or without cleft palate results from failure of the nasal and maxillary facial processes to fuse. Fusion of these processes may be affected by the amount of mesenchyme present, its rate of migration, and the distance over which this migration occurs (Lynch and Kimberling, 1981).
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Fifty percent of cleft lip patients also have cleft palate, which is a secondary effect resulting from a defect in facial prominence ...