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Cleft Lip and Cleft Palate


Simeon A. Boyadjiev Boyd

, MD, University of California, Davis

Reviewed/Revised Sep 2022
Topic Resources

An oral-facial cleft is a birth defect in which the lip, the roof of the mouth, or both do not close in the midline and remain open, creating a cleft lip and/or cleft palate. These defects are present at birth and interfere with feeding and, later, speech development.

Cleft lip, cleft lip and palate, and isolated cleft palate, are collectively termed oral clefts and are the most common congenital anomalies of the head and the neck, with a total prevalence of 2.1 per 1000 live births.

Both environmental and genetic factors have been implicated as causes. Prenatal maternal use of tobacco and alcohol may increase risk. Having one affected child increases risk of having a second affected child. Folate, taken just before becoming pregnant and through the first trimester, decreases the risk.

Oral clefts are divided into 2 groups:

  • Syndromic (30%)

  • Nonsyndromic (70%)

Syndromic oral clefts are those present in patients with recognized congenital syndromes or with multiple congenital anomalies. These oral clefts are typically caused by chromosome abnormalities and defined monogenic syndromes.

Nonsyndromic (isolated) oral clefts are those present in patients without associated anomalies or developmental delays. A number of different gene mutations can cause the phenotype, including mutations of some of the genes that are involved with syndromic oral clefts, which suggests there is significant overlap between syndromic and nonsyndromic clefts.

The cleft may vary from involvement of only the soft palate to a complete fissure of the soft and hard palates, the alveolar process of the maxilla, and the lip. The mildest form is a bifid uvula. An isolated cleft lip can occur.

A cleft palate interferes with feeding and speech development and increases the risk of ear infections. Goals of treatment are to ensure normal feeding, speech, and maxillofacial growth and to avoid formation of fistulas.


  • Clinical appearance

  • Genetic testing

A clinical geneticist should evaluate affected patients even in cases of apparent isolated congenital anomaly.

Chromosomal microarray analysis Diagnosis Chromosomal abnormalities cause various disorders. Abnormalities that affect autosomes (the 22 paired chromosomes that are alike in males and females) are more common than those that affect... read more , specific gene tests, or broader gene panel tests should be considered in the evaluation of patients with congenital craniofacial abnormalities. If the results of these tests are nondiagnostic, whole exome sequencing analysis is recommended.

Treatment of Cleft Lip and Cleft Palate

  • Surgical repair

Early treatment, pending surgical repair, depends on the specific abnormality but may include specially designed bottle nipples (to facilitate flow), dental appliances (to occlude the cleft so suckling can occur), a feeder that can be squeezed to deliver formula, taping, and an artificial palate molded to the child’s own palate. The frequent episodes of acute otitis media must be recognized and treated.

Ultimate treatment is surgical closure; however, timing of surgery, which may interfere with growth centers around the premaxilla, is somewhat controversial. For a cleft palate, a 2-stage procedure is often done. The cleft lip, nose, and soft palate are repaired during infancy (at age 3 to 6 months). Then, the residual hard palate cleft is repaired at age 15 to 18 months. Surgery can result in significant improvement, but if deformities are severe or treatment is inadequate, patients may be left with a nasal voice, compromised appearance, and a tendency to regurgitate.

Dental and orthodontic treatment, speech therapy, and genetic counseling are recommended.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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