Cleft lip: unilateral primary deformities.

The understanding and management of all aspects of unilateral cleft lip deformities continue to evolve. Just as we are entering the era of exciting advances in the understanding of the pathogenesis of craniofacial disorders, expansion of our understanding of the dynamic relationships of the structural and soft-tissue components of cleft deformities has assisted surgeons in achieving progressively improved and consistent outcomes for these patients. The anatomic and physiologic complexity of unilateral cleft lip deformities has been recognized for centuries, and generations of researchers have cumulatively contributed to our current understanding. This article examines the history, classification, anatomy, and controversies in the surgical management of unilateral cleft lip deformities, allowing surgeons to formulate a reasoned, longitudinal management plan for their patients on the basis of the available current data.