Congenital zygomatico-maxillo-mandibular fusion: a brief case report and review of literature

Fgf8 dosage regulates jaw shape and symmetry through pharyngeal-cardiac tissue relationships

BACKGROUND

Asymmetries in craniofacial anomalies are commonly observed. In the facial skeleton, the left side is more commonly and/or severely affected than the right. Such asymmetries complicate treatment options. Mechanisms underlying variation in disease severity between individuals as well as within individuals (asymmetries) are still relatively unknown.

RESULTS

Developmental reductions in fibroblast growth factor 8 (Fgf8) have a dosage dependent effect on jaw size, shape, and symmetry. Further, Fgf8 mutants have directionally asymmetric jaws with the left side being more affected than the right. Defects in lower jaw development begin with disruption to Meckel's cartilage, which is discontinuous. All skeletal elements associated with the proximal condensation are dysmorphic, exemplified by a malformed and misoriented malleus. At later stages, Fgf8 mutants exhibit syngnathia, which falls into two broad categories: bony fusion of the maxillary and mandibular alveolar ridges and zygomatico-mandibular fusion. All of these morphological defects exhibit both inter- and intra-specimen variation.

CONCLUSIONS

We hypothesize that these asymmetries are linked to heart development resulting in higher levels of Fgf8 on the right side of the face, which may buffer the right side to developmental perturbations. This mouse model may facilitate future investigations of mechanisms underlying human syngnathia and facial asymmetry.

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.

Application of computer-assisted navigation in treating congenital maxillomandibular syngnathia: A case report

BACKGROUND

Congenital maxillomandibular syngnathia is an extremely rare disorder characterized by craniofacial malformations and inability to open the mouth adequately, which leads to problems with feeding, swallowing, and breathing as well as temporomandibular joint ankylosis. The main goal of the surgery is to release the ankylosis, establish functioning mandible, and prevent re-fusion. However, surgical procedures for this disease are rarely reported.

CASE SUMMARY

Here, we report a 7-mo-old girl with bilateral maxillomandibular syngnathia. The patient presented with difficulty in feeding, breathing, sounding, and swallowing and had developmental dysplasia. For treatment, we performed bone isolation by computer-assisted navigation and used silicone to fix the wound surface to prevent refusion of bone. To our knowledge, this is the only syngnathia case in the literature treated using computer-assisted navigation. With the guidance of precise navigation, we were able to minimize operation time by at least one hour, the patient's blood vessels, nerves, and tooth germs were well protected, and excessive bleeding was avoided. After six weeks, the patient showed improvement in mouth opening and no major issues of feeding.

CONCLUSION

Application of computer-assisted navigation can significantly improve accuracy, effectiveness, and surgical safety in correcting congenital maxillomandibular syngnathia.

Ankyloglossum Superius Syndrome compromising a neonatal airway: Considerations in congenital oral airway obstructions

We report the case of a 37-week old newborn presenting on day 1 of life with an apparent congenital fusion of the tongue to the hard palate, consistent with Ankyloglossum Superius syndrome. Physical exam along with endoscopy showed apparent fusion of the floor of the mouth to the anterior hard palate displacing the tongue into the nasal cavity and obstructing the oral airway. The child was nasotracheally intubated and brought to the operating room for lysis of the fusion under binocular microscopy. We review the literature on this rare condition and provide an algorithm for evaluating the neonatal airway in the setting of congenital oral abnormalities.

Maxillomandibular Syngnathia: 3D Planning and Review of the Literature

Congenital maxillomandibular fusion or syngnathia is a rare craniofacial disorder with only 26 cases reported in the literature. We present a case of a congenital complex zygomatico-mandibular syngnathia associated with a palatal cleft, posterior maxilla and turbinate agenesia, mild hemifacial microsomia, and a disordered dental eruption. The patient has the highest age (15 years) at diagnosis described in the literature. 3D planning of the surgery was performed to study the patient's anatomy and design the necessary osteotomies to separate the jaws. En bloc removal of the fused fragment with bilateral coronoidectomy and aggressive long-term physiotherapy for 3 months led to a stable increase in mouth opening from 0 to 21 mm inter-incisor distance. The patient reported an improvement in speech, was able to eat without restriction regarding food consistency, and could maintain a good oral hygiene.

Syngnathia-Congenital Maxillomandibular fusion: Case Report and Literature Review

Congenital maxillomandibular fusion is a rare disorder of the craniofacial region. Maintenance of the airway and difficulty in feeding are the main concerns for such patients. We performed a PubMed search to identify reported cases of syngnathia. With reference to the site of fusion and corresponding anomalies, the available studies were reviewed. The maxillomandibular fusion can be anterior fusion, unilateral or bilateral fusion, and complete fusion. The condition can be an isolated problem or associated with a syndrome. The condition requires immediate attention because it can be fatal. A case of isolated unilateral syngnathia, with the detailed review of the published data, is reported.

Congenital Bilateral Zygomatico-Maxillo-Mandibular Fusion Associated With Gum Fusion

A congenial syngnathia is very rare condition. It can be simple mucosal fusion (synechiae), or complete bony fusion (synostosis) between the maxilla or zygoma and the mandible. Fusion of the ascending ramus of mandible to maxilla and zygoma is less common than fusions of the alveolar ridges of the mandible to the maxilla. Bony syngnathia is either isolated or complex in form. There are 59 cases of congenital bony syngnathia reported in the literature: the first report was by Burket in 1936. There are 16 reported cases of zygomatico-maxillo-mandibular fusion. In the reported cases, women expressed the isolated form more commonly whereas men demonstrated a more complex pattern of disease. The authors present another patient of bony syngnathia involving bilateral fusion of the ascending ramus and body of the mandible with the maxillary complex in a young man. Early surgery was performed to release the bony and soft tissue fusion on the eighth day from the baby's birth. A second operation was performed for recurrence when the baby was 2.5 months old. A customized splint, an intense postoperative program of mouth exercises, and close follow-up aims to prevent further refusion.

Ankylosis and pseudoankylosis of the temporomandibular joint in 10 dogs (1993-2015)

OBJECTIVE

To describe the clinical features and results of treatment of true ankylosis and pseudoankylosis of the temporomandibular joint in dogs.

METHODS

This study was a retrospective case series. Ten client-owned dogs that were presented for inability to open the mouth or a severely decreased range of motion of the temporomandibular joint were included. Information on the surgical procedures performed and the perioperative complications were documented. Three-dimensional printing of the skull was performed in four dogs.

RESULTS

Two dogs were diagnosed with temporomandibular joint ankylosis and seven dogs with pseudoankylosis. One dog had evidence of combined temporomandibular joint ankylosis and pseudoankylosis. Of the seven dogs with pseudoankylosis, six had an osseous fusion involving the zygomatic arch and mandible. Surgical treatment was performed in nine dogs and a revision surgery was needed in one dog. Follow-up ranged from five months to eight years (mean: 48.6 months). Eight out of nine dogs that were treated surgically regained the ability to open their mouth, but six dogs never regained a fully normal temporomandibular joint range of motion.

CLINICAL SIGNIFICANCE

Temporomandibular joint ankylosis and pseudoankylosis are uncommon in the dog. Surgical treatment for temporomandibular joint ankylosis or pseudoankylosis in dogs is a successful option and carries a prognosis dependent on patient-specific abnormalities. Computed tomography complemented with three-dimensional printing is valuable for understanding the extent of abnormalities and for preoperative planning.

Congenital bilateral syngnathia and tracheoesophageal fistula: A rare presentation

Congenital syngnathia (CS), first reported by Burket in 1936, is a rare condition, with <50 reported cases and is associated with other conditions and syndromes. CS restricts mouth opening, causing difficulty in feeding, swallowing, and respiration. This report puts forth the clinical findings and management of this challenging condition in association with tracheoesophageal fistula in a neonate.

Postnatal Diagnosis of a Baby With Multiple Rare Congenital Anomalies Including Syngnathia, Brain Dysmorphism, and Skin Pigmentation

Syngnathia is a rare congenital disorder of jaw fusion with a paucity of literature from developed countries. We present a case of an infant noted to have multiple anomalies at birth including syngnathia, microcephaly with a variant of brain abnormality between holoprosencephaly and syntelencephaly, optic nerve hypoplasia, ear canal anomalies, hemi-vertebrae, and suspected hypomelanosis of Ito. To our knowledge, this patient with syngnathia and multiple anomalies is the first to be reported, but whether they are a coincidence, a pathogenetic association, or a new syndrome remains unknown. This case is discussed with a brief review of the literature.

Children with Limited Oral Opening Can Be Safely Managed without a Tracheostomy

Objective

To describe airway management of children with limited oral opening that does not allow for routine orotracheal intubation by direct laryngoscopy. To analyze the incidence and outcome of airway compromise or loss in patients without a tracheostomy in place.

Study Design

Case series with chart review.

Setting

Tertiary children’s hospital.

Subjects

Children with limited oral opening that does not allow for routine orotracheal intubation.

Methods

Children treated at Children’s Hospitals and Clinics of Minnesota from 1997 to 2012 with severe trismus were identified and included in the study. Hospital and clinic records were reviewed.

Results

Ten children (mean age, 13 years; range, 7-17 years) were identified for inclusion into the study. A total of 109 operations requiring general anesthesia (average of 10.9 per patient; range, 0-23) were performed on patients without a tracheostomy in place. Flexible fiber-optic nasotracheal intubation was performed in 58 cases. The remainder of airway control was by mask ventilation (33 cases), various methods of orotracheal intubation (10 cases), unknown (6 cases), and laryngeal mask airway (2 cases). There was a total of 118 patient-years of follow-up without a tracheostomy tube in place (average of 11.8 years per patient). During this period, there were no episodes of acute airway compromise that resulted in neurologic deficits.

Conclusion

Children with limited oral opening that does not allow for routine orotracheal intubation with direct laryngoscopy may be safely managed without a tracheostomy, even when the child requires frequent procedures under general anesthesia.