The Cleft Palate And Lip: Embryology, Genetics, Environmental Influences, And Approaches To Surgical Repair

The cleft palate and lip is one of the most common birth defects that may or may not be syndromic. Clefting may manifest unilaterally or bilaterally with varying degrees of severity. In embryo, the upper and lower jaws were formed from the first brachial arches that descend from both sides and fuse. Many genetic loci and cell-signaling pathways have been identified with the fusion event, in which polar neural crest cells undergo the epithelial-to-mesenchymal transition. Genetic mutations, environmental teratogens, and nutrition have been associated with the cleft palate and lip. The extracellular matrix has been extensively studied to understand cell-cell communication and is crucial in tissue engineering. The gold standard today for palatal reconstruction remains to be an autogenous graft from the anterior iliac crest. Autogenous bone grafts have many disadvantages such as donor site morbidity. New approaches in tissue engineering involving stems cells, growth factors, and biomaterial scaffolding have been identified to avoid autogenous bone grafts. Mesenchymal cells may be harvested from dental tissue and adipocytes. Three-dimensional printing and computer-aided design are becoming widely used in oral surgery. More research are underway to overcome the challenges in soft tissue reconstruction of the soft palate.