Trigeminal nerve distribution area

All kinds of control of our life activities come from our trigeminal nerve and central nervous system. When the nerve sends out a signal, it is transmitted to various parts of the body by the trigeminal nerve. Only then can we feel that the brain has given orders to the limbs. The trigeminal nerve is distributed in various parts of our body, generally from the inside to the outside. So where is the distribution area of ​​the trigeminal nerve?

Branches and distribution of the trigeminal nerve:

Three large branches composed of peripheral processes extend forward from the trigeminal ganglion, which are the ophthalmic nerve, maxillary nerve and mandibular nerve from the inside to the outside.

Optic nerve

The ophthalmic nerve (n.ophthalmicus) is the smallest of the three branches and contains only general somatic sensory fibers. The ophthalmic nerve enters the lateral wall of the cavernous sinus forward, enters the orbit through the superior orbital fissure, and is distributed in the skin of the forehead, upper eyelid and nasal dorsum, as well as the eyeball, lacrimal gland, conjunctiva and part of the nasal mucosa).

(1) The lacrimal nerve is small and runs along the lateral wall of the orbit and the upper edge of the lateral rectus muscle to the lacrimal gland and is distributed in the skin of the lacrimal gland and upper eyelid.

(2) The frontal nerve is relatively large and is located above the levator palpebrae superioris muscle. It is divided into 2 to 3 branches. The supraorbital nerve is relatively large and passes through the supraorbital notch. Its branches are distributed in the skin of the forehead.

(3) The nasociliary nerve runs deep to the superior rectus muscle, passes over the optic nerve and reaches the medial wall of the orbit. This nerve has many branches, which are distributed in the eyeball, sphenoid sinus, ethmoid sinus, lower eyelid, lacrimal sac, nasal mucosa and nasal dorsum skin.

Maxillary nerve

The maxillary nerve (n.maxillaris) is also a general somatic sensory nerve. After it is emitted from the trigeminal ganglion, it immediately enters the lateral wall of the cavernous sinus, then exits the skull through the foramen rotundum, enters the pterygopalatine fossa, and then enters the orbit through the infraorbital fissure to continue as the infraorbital nerve. The branches of the maxillary nerve are distributed in the maxillary teeth, gums, maxillary sinuses, nasal and oral mucosa, facial skin between the palpebral fissures, and part of the dura mater.

(1) The infraorbital nerve is the terminal branch of the maxillary nerve. It passes through the infraorbital groove, infraorbital canal, and infraorbital foramen to the face, where it divides into several branches and is distributed to the skin of the lower eyelid, wing of the nose, and upper lip.

(2) The zygomatic nerve originates from the pterygopalatine fossa, enters the orbit through the inferior orbital fissure, penetrates the lateral wall of the orbit to the face, and its branches are distributed in the zygomatic and temporal skin. During its journey, the zygomatic nerve sends out a small branch composed of parasympathetic postganglionic nerve fibers that anastomose with the lacrimal nerve. This branch enters the lacrimal gland and controls lacrimal secretion.

(3) The superior alveolar nerve is divided into the anterior, middle, and posterior superior alveolar branches. There are 2 to 3 posterior branches. After they emerge from the maxillary nerve in the pterygopalatine fossa, they pass through the back of the mandibular body and enter the bone. The anterior and middle branches of the upper alveolar nerve branch off from the infraorbital nerve, and the three branches anastomose in the maxillary alveolar bone to form the upper dental plexus, with branches distributed in the maxillary sinus, maxillary teeth and gums.

(4) The pterygopalatine nerve, also known as the ganglion branch, consists of 2 to 3 nerve branches that originate from the main trunk of the maxillary nerve through a section above the pterygopalatine fossa, connect downward to the pterygopalatine ganglion, and are then distributed to the mucosa of the palate and nasal cavity and the palatine tonsils.

Mandibular nerve

The mandibular nerve (n. mandibularis) is a mixed nerve and the largest of the three branches. After emerging from the trigeminal ganglion, it exits the cranial cavity through the oval foramen to reach the infratemporal fossa and immediately divides into many branches. Among them, special visceral motor fibers innervate the muscles of mastication. Generally, somatic sensory fibers are distributed in the mandibular teeth, gums, the anterior 2/3 of the tongue, the mucosa of the floor of the mouth, as well as the ear-temporal area and the facial skin below the oral fissure.

(1) The auriculotemporal nerve originates from two roots, wraps around the middle meningeal artery and merges into one trunk, which penetrates the parotid gland parenchyma and runs along with the superficial temporal artery. Its branches extend upward and are distributed in front of the auricle, the temporal skin, and the parotid gland.

(2) The buccal nerve runs along the outside of the buccinator muscle, passes through the muscle and distributes to the buccal mucosa and the skin of the cheek area to the corners of the mouth.

(3) The lingual nerve is in front of the inferior alveolar nerve and descends deep to the lateral pterygoid muscle. Along the way, the chorda tympani of the facial nerve joins this nerve from the back. After that, it passes over the superficial surface of the medial pterygoid muscle to reach the top of the submandibular gland, and then runs along the surface of the hyoglossus muscle to the tip of the tongue. The branches of the lingual nerve are distributed in the mucosa of the floor of the mouth and the front 2/3 of the tongue, receiving stimulation from general somatic sensations.

(4) The inferior alveolar nerve is a mixed nerve containing general somatic sensory fibers and special visceral motor fibers. The inferior alveolar nerve is located behind the lingual nerve and runs down along the lateral surface of the medial pterygoid muscle. Its special visceral motor fibers branch out to innervate the mylohyoid muscle and the anterior belly of the digastric muscle. General somatic sensory fibers enter the mandibular canal through the mandibular foramen. The branches in the mandibular canal form the lower dental plexus, and the branches are distributed in the mandibular teeth and gums. Its terminal branch passes through the mental foramen and is called the mental nerve, which is distributed in the skin and mucous membrane of the chin and lower lip.

(5) The masticatory nerve is a special visceral motor nerve with several branches innervating all the masticatory muscles.