Cleft lip can be an isolated event or can be found in conjunction with a cleft palate. It is caused by the failure of the normal structures to fuse together during the formation of the lip. The cleft is an opening in the lip. The skin, muscle, and oral lining tissue is present but has not fused leaving an opening.

Cleft lips occur more often on the left side rather than the right side for reasons that we don’t understand. More than half of cleft lips occur with a cleft palate where there is a failure of the two sides of the roof of the mouth to fuse in the midline to form a complete palate. Clefts of the lip, incomplete or complete, are associated with some degree of nasal distortion. The children with incomplete cleft lips have a smaller nasal deformity than the children with complete cleft lips.

Clefts that involve the lip and the palate are more significant in that cleft palates can affect feeding, weight gain, middle ear function, speech and facial growth. Each of these issues may be noted at different ages, i.e. difficulty feeding and middle ear dysfunction are infant and early childhood issues. Speech difficulties present themselves later around two years of age. Facial growth and dental occlusion are preteen or adolescent issues. A craniofacial team is essential to provide the children and their families the care they need to give the best result.