Description
- congenital malformation of the upper lip and/or oral cavity disrupting normal facial structure and oromotor function
Definitions
- World Health Organization definitions from the International Perinatal Database of Typical Oral Clefts (IPDTOC)
- cleft lip and palate: congenital malformation with partial or complete clefting of upper lip and alveolar ridge and/or hard palate, not including the oral cleft palate of holoprosencephaly
- cleft lip: congenital malformation with partial or complete clefting of upper lip, not including median cleft lip (holoprosencephaly)
- cleft palate: congenital malformation with closure defect of hard and/or soft palate behind foramen incisivum without cleft lip (excluding submucous cleft palate, occult cleft palate, and cleft uvula)
- Pierre Robin sequence: cleft palate associated with significant micrognathia, with or without retroposition of the tongue (glossoptosis) or respiratory distress
Types
- cleft lip with or without cleft palate
- appears to develop from malformation of fetal primary palate with or without secondary palate malformation
- 68% to 86% of cleft lip cases associated with cleft palate
- other genetic anomalies (syndromic) in 14% to 30% of cases
- subtypes include
- microform cleft (dehiscence of orbicularis muscle with vermilion notching but intact overlying skin)
- cleft lip and alveolus
- incomplete unilateral cleft lip and palate (less severe congenital scar, notch in vermillion border, or partial clefting)
- complete unilateral cleft lip and palate
- complete bilateral cleft lip and palate
- cleft palate alone (lip not affected)
- appears to develop from malformation of fetal secondary palate
- can range from submucous clefting to complete bilateral clefting through maxillary alveolus
- other genetic anomalies (syndromic) in 42% to 54% of cases
Who is most affected
- cleft palate alone twice as common in female infants
- cleft lip with or without cleft palate more common in male infants and usually more severe than in female infants
Incidence/prevalence
- 1 in 700 live births overall report to have orofacial clefting (cleft lip and/or palate)
- reported prevalence for orofacial clefts varies worldwide
- 1.3 to 25.3 per 10,000 live births for cleft palate alone
- 3.4 to 22.9 per 10,000 live births for cleft lip, with or without cleft palate
Likely risk factors
Parental exposures:
- maternal factors
- history of fever
- cold without a fever
- history of skin disease
- maternal passive smoking
- maternal negative life events
- maternal use of antipyretics or analgesics
- anti-infectious drugs
- antiepileptics
- maternal occupational exposure to
- organic solvents
- heavy metals
- pesticides
- paternal factors associated with increased risk for
- orofacial clefting
- paternal alcohol consumption
- paternal smoking
- other factors
- pregestational hypertension
- lower parental education level
- maternal Western diet
- low myo-inositol level in mother or child
- low red blood cell zinc concentration in child
Hereditary risk factors
- family history of first-degree relative with oral cleft MTHFR C677T polymorphism with TT genotype
