Syngnathia

(Congenital fusion of the maxillary)

Very rare. Congenital fusion of maxillary: gums are merged by fibrous tissue (alveolar adhesions) or fibrocartilaginous (real syngnathia).

It is sometimes associated with other malformations such as retrognathia, aglossia, hemifacial microsomia, malformation of the temporomandibular joint or cleft palate (see syndromes: Dobrow, orofaciodigital, fossa pterigyum, van der Woude).



The treatment is surgical


Laster classification:


Type 1a: simple anterior syngnathia

simple fusion of the alveoloar processes

Type 1b: complex anterior syngnathia

fusion of alveolar processes associated with other anomalies of the head and the neck

Type 2a: simple mandibulo-zygomatic syngnathia

fusion of the mandibule to the zygomatic complex only leading to mandibular syngnathia

Type 2b: complex mandibulo-zygomatic syngnathia

fusion of the mandibule to the zygomatic complex associated with other anomalies of the head and the neck


Anesthetic implications:

difficult intubation, which can only be done by nasal route: initial placement of a nasopharyngeal airway to ensure oxygenation andinhalation anesthesia while attempting intubation under fiberscopic control via the contralateral nostril. Otherwise, temporary tracheostomy. In case of need for neonatal resuscitation, use of a nasopharyngeal airway.


nasopharyngeal tube into left nostril (oxygen and sevoflurane in a spontaneously breathing neonate), and
fiberoptic intubation via the right nostril (note the use of some jaw-thrust to lift the epiglottis from the pharyngeal wall)


References : 

-         Alfery DD, Ward CF, Harwood IR, Mannino FL.
Airway management for a neonate with congenital fusion of the jaws.
Anesthesiology 1979; 51: 340-2.

-        Seraj MA, Yousif M, Channa B.
Anaesthetic management of congenital fusio of the jws in a neonate.
Anaesthesia 1984; 39: 695-8.

-        Svee A, Frykholm P, Linder A et al.
Early release of interalveolar synechiae under general anaesthesia through fiberscopic nasal intubation.
J Craniofac Surg 2002; 23:e299-302

-        Broome M, Vial Y, Jaquemont S, Sergi C, Kamnasaran D, Giannoni E.
Complete maxiloo-mandibular syngnathia in a newborn with multiple congenital malformations.
Pediatrics  & Neonatology; 2013

-        Patel K, Ponde V.
Airway management in a child with partial mandibulo-maxillary fusion.
Indian J Anaesth 2016; 60: 961-3.

-        Panda S, Sikka K, Punj J, Sharma SC.
Bilateral congenital alveolar synechiae: a rare cause of trismus.
Maxillofacial Plast Reconstr Surg 2016; 38: 8 DOI 10.1186/s40902-016-0056-2


Updated: January 2019