Mandibular recession, divided into congenital mandibular recession and acquired mandibular recession, congenital factors are mostly related to genetics, mainly including dental and maxillofacial malformations, i.e. recession caused by underdevelopment of the mandible. It may also be caused by trauma before the age of 18, especially in childhood, if the joint has been traumatized, which can cause underdevelopment or malformation of the mandible, affecting the development of the mandible and leading to a small chin, i.e., receding jaw. In addition, orthodontics is less likely to result in jaw recession and needs to be examined or treated on a case-by-case basis.