A cleft lip is a defect (gap) between the lip and or nostril edges that may occur commonly in up to 1/1000 newborns.

A cleft palate is a hole in either the hard and/or soft palate due to failure of these structures to fuse in the midline during fetal growth.

Clefting of the lip almost invariably involves the nose, where the rim of the nose is often malpositioned.

Velopharyngeal insufficiency (VPI) occurs when the soft palate can not effectively close off the connection between the nose and the mouth allowing air to escape through the nose.