[Solitary upper incisor, hypopituitarism and monosomy 18p chromosome aberration].

A prepubertal boy with hypopituitarism, mental retardation, dysmorphia and solitary maxillary central incisor is described, karyotypic studies showed deletion of the short arm of chromosome 18 (46, XY, del (18) (p11). It is suggested that caryotypic studies is of interest among the patients with midline defects and/or hypopituitarism.