The scope of this page is cleft lip and palate in children from birth through school age (to 21 years). Some content is also relevant to individuals with velopharyngeal inadequacy, secondary to various other etiologies.
Cleft Lip and Palate Evidence Map for summaries of the available research on this topic.
Craniofacial conditions, including cleft lip and palate, are congenital structural anomalies caused by atypical embryological development. Craniofacial differences are a result of interruption in embryologic growth between the 4th and 10th week of the developing embryo or fetus (Peterson-Falzone, Hardin-Jones, & Karnell, 2010).
Clefts are described based on the structures involved (lip, alveolus, hard palate, soft palate), laterality (unilateral left, unilateral right, or bilateral), and severity (width and extent of structures involved). Clefts can be isolated (cleft lip only or cleft palate only), or they can occur in combination. They can be unilateral or bilateral, and they can be complete or incomplete.
Figure 1 contains images of the most common types of cleft affecting the palate, along with a labeled image of intact structures. The primary palate is the triangular area of the hard palate anterior to the incisive foramen and includes a portion of the alveolar ridge. The secondary palate consists of the remaining hard palate and all of the soft palate.
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Figure 1: Representation of the most common types of cleft affecting the palate. (a) Unilateral cleft lip with alveolar involvement; (b) bilateral cleft lip with alveolar involvement; (c) unilateral cleft lip associated with cleft palate; (d) bilateral cleft lip and palate; (e) cleft palate only (© Copyright Brito, Meira, Kobayashi, & Passos-Bueno, 2012).
Palatal clefts can be overt or submucous. An overt palatal cleft is visibly open and can be observed on intraoral inspection. In a submucous cleft palate (SMCP), oral mucosa is intact, but the underlying velar musculature has failed to attach at midline. The cleft is not visibly open and often is not obvious on intraoral inspection. There are three signs of an SMCP: (a) zona pellucida—a blue discoloration due to levator veli palatini muscle diastasis (i.e., separation in the midline); (b) a bifid uvula; and (c) a palpable bony notch at the edge of the hard palate.
Another type of SMCP, referred to as an occult (hidden) submucous cleft palate (OSMCP) has no visual oral manifestations and can be diagnosed only by direct observation during surgery or by magnetic resonance imaging (MRI). Nasendoscopy may demonstrate a concave or flattened nasal surface of the palate, indicating possible diastasis and/or absence of the musculus uvulae muscle.
Cleft lip and cleft palate can be associated with a large number of craniofacial and genetic sequences or syndromes, some of which are rare. Some examples include the following:
- 22q11.2 deletion syndrome (a.k.a. velocardiofacial syndrome [VCFS] and DiGeorge sequence)
- Stickler syndrome
- Pierre Robin sequence
- Van der Woude syndrome
- Treacher-Collins syndrome
- Craniofacial microsomia (spectrum of disorders, including Goldenhar syndrome)
- Neonatal Abstinence Syndrome (NAS), which includes Fetal Alcohol Spectrum Disorder (FASD)