Nederlands Tijdschrift voor Tandheelkunde vol:115 issue:2 pages:101-4
Non-syndromal orofacial clefts are congenital anomalies with a high incidence of heterogeneous origin. The condition is usually multifactorially determined, caused by interaction between multiple genetic and environmental factors. So far, only a few causal factors have been identified. Even in genetically identical individuals like monozygotic twins, the orofacial cleft is usually not fully concordant. As an illustration of non-syndromal orofacial clefts, monozygotic twin brothers with orofacial clefts which are not fully concordant are presented.