Congenital bony syngnathia with unilateral palatal shelf and soft palate agenesis.

Congenital fusion of upper and lower jaw is rare. Only 35 bony syngnathia have been reported up to date, and 9 of them revealed posterior topography. A 10-day-old female infant with facial asymmetry, limited mouth opening, and cardiac murmurs is presented. The radiological findings revealed congenital bony fusion of right coronoid process of the mandible to posterior maxillary region and right palatal shelf agenesis of palatal bone, which seems to be the first case in the literature. Classification systems of bony syngnathia and applied treatment procedures for palatal closure and release of the bony fusion are discussed.