Oblique facial clefts: case report.

In a material of about 3,600 facial clefts eleven oblique clefts were observed (3.1%). The most frequent types were the medial oro-ocular and naso-ocular clefts and their combinations. There were two atypical cases and one lateral oro-ocular variety. The oblique clefts were frequently associated with other types of clefts and/or more distant anomalies. No genetic chromosomal or environmental factors were found to explain their etiology. Amniotic bands could possibly be thought to be responsible for the severe malformations in two instances. The lacrimal apparatus was always involved to some degree with the exception of a few incomplete forms. In the alveolar arch the cleft seemed to be situated between the medial incisor and the canine.