Cleft lip and palate is the most frequent congenital oral dysmophosis (1/600 births). They can be associated with polyformative syndromes. The aetiology is most often unknown, but heredity is still a predominant factor. These clefts result from an absence or insufficient fusion of the different facial buds occurring from the fifth to the 7th week of intrauterine life. They can have several forms. The treatment of cleft lip and palate requires multidisciplinary management. When orthodontics is lacking, the prosthesis takes over. Combined with maxillofacial surgery, the results are spectacular.