Branches of Mandibular Nerve — Posterior Division
Character
The posterior division is the larger division of the mandibular nerve. It is predominantly sensory with one motor component (nerve to mylohyoid from inferior alveolar).
It passes downward and backward, medial to the lateral pterygoid, then between the sphenomandibular ligament and the ramus of mandible.
Branches
| Branch | Type | Key Features |
|---|---|---|
| Auriculotemporal nerve | Sensory | Two roots encircle middle meningeal artery; carries parasympathetic fibres from otic ganglion to parotid |
| Lingual nerve | Sensory | Joined by chorda tympani (CN VII); supplies tongue anterior 2/3 general sensation + floor of mouth |
| Inferior alveolar nerve | Mixed (mainly sensory) | Enters mandibular canal; gives mental nerve; gives nerve to mylohyoid before entry |
Auriculotemporal Nerve — Detail
- Origin: Two roots from the posterior division which encircle the middle meningeal artery
- Course: Passes behind the neck of mandible → ascends between the auricle and the condyle of mandible → crosses the root of the zygoma → enters the temporal region
- Branches and distribution:
| Branch | Area |
|---|---|
| Articular branch | Temporomandibular joint |
| Parotid branches | Parasympathetic secretomotor to parotid gland (fibres from otic ganglion) |
| Anterior auricular branches | Skin of tragus and upper part of auricle |
| Branches to external acoustic meatus | Skin of EAM and tympanic membrane (outer surface) |
| Superficial temporal branches | Skin of temple |
Clinical: Frey’s syndrome (auriculotemporal nerve syndrome) — after parotidectomy, regenerating parasympathetic fibres aberrantly innervate sweat glands → gustatory sweating (sweating over cheek during eating).
Lingual Nerve — Detail
- Origin: From posterior division of V3, in the infratemporal fossa
- Course: Descends between medial pterygoid and ramus of mandible → passes forward below the mucous membrane of the floor of the mouth → crosses the submandibular duct (Wharton’s duct) twice (first lateral, then medial) → supplies the tongue
- Joined by chorda tympani (branch of facial nerve CN VII): joins lingual nerve at the angle between medial pterygoid and ramus → adds taste fibres (anterior 2/3 tongue) and preganglionic parasympathetic fibres (to submandibular ganglion → submandibular and sublingual glands)
- Distribution: General sensation to anterior 2/3 of tongue, floor of mouth, lingual gingiva of lower teeth
Inferior Alveolar Nerve — Summary
- Largest branch of posterior division
- Enters mandibular foramen after giving off nerve to mylohyoid
- Runs through mandibular canal supplying lower teeth
- Terminates as mental nerve (exits mental foramen → supplies chin and lower lip)
- (Detailed note: Inferior Alveolar Nerve — Course and Applied Anatomy)
Nerve to Mylohyoid
- Arises from inferior alveolar nerve just before it enters the mandibular foramen
- Runs in the mylohyoid groove on the medial surface of ramus of mandible
- Supplies: mylohyoid and anterior belly of digastric
Mandibular Nerve | Branches of Mandibular Nerve — Anterior Division | Inferior Alveolar Nerve — Course and Applied Anatomy | Chorda Tympani — Course and Distribution