Syngnathia-Congenital Maxillomandibular fusion: Case Report and Literature Review

Application of Computer-Assisted Preoperative Planning in Treating Congenital Bilateral Zygomatico-Maxillo-Mandibular Fusion: A Case Report and Literature Review

Congenital fusion of the jaws (syngnathia) is a rare facial malformation with an unknown etiology. This disease may vary in severity with adhesion of soft tissue and bony fusion. It can be anterior fusion, unilateral or bilateral fusion, and complete fusion. The main problem of these patients is the difficulty of airway maintenance and feeding, and the most common postoperative complication is the relapse of bony fusion. Here, we report a young male patient with bony syngnathia, involving bilateral fusion of the ascending ramus and body of the mandible with the maxillary complex. We performed bone isolation by computer-assisted preoperative planning and used an insertional temporalis flap to fix the wound surface to prevent refusion of bone.

Congenital Maxillomandibular Syngnathia: Review of Literature and Proposed New Classification System

PURPOSE

Maxillomandibular fusion (syngnathia) is a rare craniofacial anomaly. It occurs as either fibrous (synechiae) or bony (synostosis) fusion of jaw or fusion of mandible to zygoma, tuberosity, hard palate and temporal bone. There are several documentations delineating this condition but owing to its varying presentation, association with both intraoral and extraoral anomalies and syndromes, reviewing it has been as uphill task. The non-unanimous description of cases in the literature and the use of different nomenclatures make it difficult to classify this condition.

METHODS

Extensive search of the literature was done from the year 1936 to 2018 which included a total of 118 cases with 62 cases of bony fusion, 48 cases of fibrous fusion and 8 cases of combined fusion, i.e., fibrous on one site and bony on another side.

RESULTS

This paper proposes a novel, simple and explicit classification system on the basis of nature of fusing tissues, location and extent, association with syndrome after reviewing the existing literature. Furthermore, this review reports 4 new cases of syngnathia along with their clinical, radiographic features and their management protocol.

CONCLUSIONS

This classification can be generalized to all the cases of syngnathia and can further facilitate in its appropriate diagnosis and treatment plan.

Vertical Distraction for the Treatment of Congenital Syngnathia

Congenital syngnathia is a very rare condition that presents with several unique challenges. There is no consensus on the best operative approach to manage this condition. Readhesion of surgically separated tissues is a relatively common occurrence. The authors propose that the use of a vertical distraction technique helps maintain adequate separation to prevent relapse of the bony fusion. Long-term follow-up will be required to follow mandibular growth and implications of this treatment option.

Syngnathia in Spectrum of Oromandibular Limb Hypogenesis Syndrome

Syngnathia is a rare facial anomaly associated with neonatal problems, including a compromised airway, and the inability to take in solids and/or liquids. Syngnathia is included within the spectrum of oromandibular limb hypogenesis syndrome, an extremely rare condition characterized by varying degrees of congenital malformation involving the tongue, mandible, and limbs. In this report, we describe the case of a 41-day-old Caucasian female infant who was unable to open her mouth beginning at birth. The authors performed osteotomies to separate fused bone, and placed a bite block at the osteotomy sites to prevent bone fusion recurrence. At 2 years of follow-up patient remained with 14 mm of mouth opening.