[A single central maxillary incisor in the midline as a mild form of holoprosencephaly].
Besides the hypotelorism the mildest form of holoprosencephaly is the solitary incisor. In the case described, the girl had only high palate and torus palatinus, but no other alteration in the midline. One of her brothers had cleft lip and palate, which indicates genetical determination. The girl has been orthodontically treated.