Submandibular ganglion
Encyclopedia
The submandibular ganglion (or submaxillary ganglion in older texts) is part of the human autonomic nervous system
. It is one of four parasympathetic ganglia
of the head and neck. (The others are the otic ganglion
, pterygopalatine ganglion
, and ciliary ganglion
).
and sublingual gland
.
, on the hyoglossus muscle, near the posterior border of the mylohyoid muscle
.
The ganglion 'hangs' by two nerve filaments from the lower border of the lingual nerve
(itself a branch of the mandibular nerve
, CN V3). It is suspended from the lingual nerve by two filaments, one anterior and one posterior. Through the posterior of these it receives a branch from the chorda tympani
nerve which runs in the sheath of the lingual nerve.
Autonomic nervous system
The autonomic nervous system is the part of the peripheral nervous system that acts as a control system functioning largely below the level of consciousness, and controls visceral functions. The ANS affects heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils,...
. It is one of four parasympathetic ganglia
Parasympathetic ganglia
Parasympathetic ganglia are the autonomic ganglia of the parasympathetic nervous system. Most are small terminal ganglia or intramural ganglia, so named because they lie near or within the organs they innervate...
of the head and neck. (The others are the otic ganglion
Otic ganglion
The otic ganglion is a small, oval shaped, flattened parasympathetic ganglion of a reddish-gray color, located immediately below the foramen ovale in the infratemporal fossa. It gives innervation to the parotid gland for salivation....
, pterygopalatine ganglion
Pterygopalatine ganglion
The pterygopalatine ganglion is a parasympathetic ganglion found in the pterygopalatine fossa. It is one of four parasympathetic ganglia of the head and neck....
, and ciliary ganglion
Ciliary ganglion
The ciliary ganglion is a parasympathetic ganglion located in the posterior orbit. It measures 1–2 millimeters in diameter and contains approximately 2,500 neurons. Preganglionic axons from the Edinger-Westphal nucleus travel along the oculomotor nerve and form synapses with these cells...
).
Function
The submandibular ganglion is responsible for innervation of two salivary glands: the submandibular glandSubmandibular gland
The paired submandibular glands are salivary glands located beneath the floor of the mouth. In humans, they account for 70% of the salivary volume and weigh about 15 grams. Unstimulated in humans, the percentage contribution to whole saliva; ~25% Parotid, Submandibular and Sublingual ~ 67% and...
and sublingual gland
Sublingual gland
The sublingual glands are salivary glands in the mouth.They lie anterior to the submandibular gland under the tongue, beneath the mucous membrane of the floor of the mouth.They are drained by 8-20 excretory ducts called the ducts of Rivinus....
.
Location and relations
The submandibular ganglion is small and fusiform in shape. It is situated above the deep portion of the submandibular glandSubmandibular gland
The paired submandibular glands are salivary glands located beneath the floor of the mouth. In humans, they account for 70% of the salivary volume and weigh about 15 grams. Unstimulated in humans, the percentage contribution to whole saliva; ~25% Parotid, Submandibular and Sublingual ~ 67% and...
, on the hyoglossus muscle, near the posterior border of the mylohyoid muscle
Mylohyoid muscle
The mylohyoid muscle is a muscle running from the mandible to the hyoid bone, forming the floor of the oral cavity. It is named for its two attachments, with the prefix "mylo" coming from the Greek word for "molar". These muscles are mesodermal in origin...
.
The ganglion 'hangs' by two nerve filaments from the lower border of the lingual nerve
Lingual nerve
The lingual nerve is a branch of the mandibular nerve , itself a branch of the trigeminal nerve, which supplies sensory innervation to the tongue...
(itself a branch of the mandibular nerve
Mandibular nerve
The mandibular nerve is the largest of the three branches of the trigeminal nerve.-Roots:It is made up of two roots:* a large sensory root proceeding from the inferior angle of the trigeminal ganglion....
, CN V3). It is suspended from the lingual nerve by two filaments, one anterior and one posterior. Through the posterior of these it receives a branch from the chorda tympani
Chorda tympani
The chorda tympani is a nerve that branches from the facial nerve inside the facial canal, just before the facial nerve exits the skull via the Stylomastoid foramen...
nerve which runs in the sheath of the lingual nerve.
Fibers
Like other parasympathetic ganglia of the head and neck, the submandibular ganglion is the site of synapse for parasympathetic fibers and carries other types of nerve fiber that do not synapse in the ganglion. In summary, the fibers carried in the ganglion are:- Sympathetic fibers from the external carotid plexus, via the facial nerveFacial nerveThe facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...
and its branches. These do not synapse in this ganglion. - Preganglionic parasympathetic fibers from the superior salivatory nucleus of the medulla oblongataMedulla oblongataThe medulla oblongata is the lower half of the brainstem. In discussions of neurology and similar contexts where no ambiguity will result, it is often referred to as simply the medulla...
, via the chorda tympaniChorda tympaniThe chorda tympani is a nerve that branches from the facial nerve inside the facial canal, just before the facial nerve exits the skull via the Stylomastoid foramen...
and lingual nerveLingual nerveThe lingual nerve is a branch of the mandibular nerve , itself a branch of the trigeminal nerve, which supplies sensory innervation to the tongue...
, which synapse at the origin of: - Postganglionic parasympathetic fibers to the oral mucosaOral mucosaThe oral mucosa is the mucous membrane epithelium of the mouth. It can be divided into three categories.*Masticatory mucosa, para-keratinized stratified squamous epithelium, found on the dorsum of the tongue, hard palate and attached gingiva....
and the submandibularSubmandibular glandThe paired submandibular glands are salivary glands located beneath the floor of the mouth. In humans, they account for 70% of the salivary volume and weigh about 15 grams. Unstimulated in humans, the percentage contribution to whole saliva; ~25% Parotid, Submandibular and Sublingual ~ 67% and...
and sublingualSublingual glandThe sublingual glands are salivary glands in the mouth.They lie anterior to the submandibular gland under the tongue, beneath the mucous membrane of the floor of the mouth.They are drained by 8-20 excretory ducts called the ducts of Rivinus....
salivary glands.They are secretomotor to these glands.