A positive family history has been found in 9.1% of cleft palate subjects in Sri Lanka.[ 9 ] The incidence of cleft lip and palate has been doubled during the last 50 years and tripled during the last 100 years.[ 10 ] A 30-year follow-up study showed a clear trend of rapid increase in cleft lip and palate in Finland.[ 11 ] Etiology of cleft lip and palate The etiology of cleft lip and palate is believed to be multifactorial.
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