Congenital fusion of the maxilla and mandible (congenital bony syngnathia).

A rare case of syngnathia (maxillomandibular fusion) is described in a 2-year-old boy who presented from a rural area of Saudi Arabia. The child had the problem since birth and had undergone two surgical attempts to release the fusion at another institution but both had failed and recurrence occurred. In the authors' institute, the patient underwent two separate surgical procedures at the age of 2 and 3 years. Both procedures were followed by a period of aggressive physiotherapy, but the patient presented with re-fusion of the mandible and the maxilla 1 year after the first operation and 5 months after the second operation. It was decided to defer treatment until puberty. The cause of the relapse may be the high osteogenic potential because of his youth or the failure of the parents to maintain the active physiotherapy protocol because they live in a rural area and close follow-up was difficult. A possible genetic predisposition for bone formation at this site should be investigated.