Facial malformations and asymmetries caused by the first and second branchial arch syndrome

: The first and second branchial arch syndrome is a congenital affection, among whom one can range as well hereditary as non-hereditary entities. They always cause a badly mutilating facial asymmetry. In this article, the first and second branchial arch syndrome were divided in hemifacial and bilateral dysostoses. We pointed out the hemifacial microsomia, the most occurring entity in these series. From two case reports, we attempt to give a treatment synopsis of this syndrome, which is always done by a multi-disciplinary team, including dentists, orthodontists, maxillofacial surgeons and plastic surgeons.