has characteristic has characteristic isolated congenital syngnathia https://github.com/monarch-initiative/mondo/issues/4069 https://www.malacards.org/card/isolated_congenital_syngnathia Isolated congenital syngnathia is a very rare developmental defect during embryogenesis characterized by varying degrees of congenital fusion (ranging from simple mucosal adhesions to extensive bony fusion) of mandible to maxilla that is not associated with any other malformations. Patients present with mouth opening limitation (which could range from severe to minimal restriction) that typically results in feeding, swallowing and/or respiratory difficulties which may lead to failure to thive, malnutrition and/or temporomandibular joint ankylosis. UMLS:C4706392 SCTID:763317002 Orphanet:141214 isolated congenital maxillomandibular fusion GARD:0019962 MEDGEN:1635309 MONDO:0015409 obsolete syndrome or malformation associated with head and neck malformations congenital disorder of development or morphogenesis otorhinolaryngologic disease