Mirror-image Bilateral Complete and Incomplete Cleft Lip and Alveolus in Monozygotic Twins: A Case Report

Cleft lip and/or palate (CL/P) represent one of the most common congenital malformations in the oral and maxillofacial region, and various factors are associated with the development of CL/P and its subtypes. Despite an increased concordance rate in monozygotic twins, mirror-image cleft formations represent a very rare phenotype, for which only very few case reports exist in the literature. The present case report describes a female pair of monozygotic twins from Germany who were born with mirror-image bilateral complete and incomplete cleft lip and alveolus.