Nervous system · Head and neck
Lingual nerve !
The lingual nerve gives touch and taste to the front of the tongue; it lies close to the lower wisdom tooth, so its removal can injure it.
Opens in the Durgical app, no sign-up needed.
What it is
A V3 branch to the tongue, joined by the chorda tympani from the facial nerve.
What it does
Feeling and taste of the front of the tongue; saliva from two glands.
Key facts
- Roots
- V3; joined by the chorda tympani (VII)
- Moves
- Carries parasympathetic fibres (VII) to the submandibular ganglion -> submandibular and sublingual glands
- Feeling from
- General sensation (V3) and taste (VII) of the anterior two thirds of the tongue
Relations
- Course
- Branch of the posterior trunk of the V3 mandibular nerve in the infratemporal fossa; joined by the chorda tympani, it descends between the medial pterygoid and the ramus in front of the inferior alveolar nerve, passes just inside the third molar, then runs forward on the hyoglossus, crosses the submandibular duct and enters the tongue
- Lateral
- The ramus of the mandible and, lower down, the inner surface of the jaw at the third molar
- Medial
- The medial pterygoid above; the hyoglossus and the side of the tongue below
- Below
- The submandibular ganglion hanging from it, and the deep part of the submandibular gland with its duct
How to find it
It can sometimes be felt against the bone under the mucosa of the floor of the mouth, beside the lower third molar; from there it runs forward in the floor of the mouth beside the submandibular duct.
Examination
- Light touch on the front of the tongue on each side (general sensation, V3)
- Taste of sweet or salty solutions on the front two thirds of each side of the tongue (chorda tympani, VII)
On imaging
Not seen on radiographs or routine CT, as it runs in soft tissue. Before lower third molar surgery, a panoramic radiograph or cone beam CT assesses the tooth, the inferior alveolar canal and the thin lingual bone plate, the landmark for the nerve's risk. After an injury, high-resolution MR neurography can show a swollen or cut nerve or a neuroma in selected cases.
Clinical notes
- Injury in third molar surgery or from a block usually recovers, but lasting numbness, altered taste or painful tingling of the tongue can follow
- In removal of the submandibular gland the nerve is identified where it crosses the duct and gives its connection to the ganglion, before the duct is tied
- Taste loss on the front of the tongue with normal touch places the lesion in the chorda tympani or the facial nerve (VII), not the lingual nerve
Anatomical variants
- Its height beside the lower third molar varies: in some people it lies at or above the bone crest, against the inner plate, where an incision or a retractor can easily reach it
Related conditions
Test yourself
Think of the answer, then tap the question to see it.
Why is the lingual nerve at risk in lower third molar surgery, and what is the deficit?
It lies just under the mucosa inside the third molar; injury numbs the tongue and loses taste on that side.
Which nerve joins the lingual nerve to bring taste from the front of the tongue?
The chorda tympani of the facial nerve (VII), which also carries parasympathetic fibres to the submandibular ganglion.
How does the lingual nerve relate to the submandibular duct?
It crosses the duct, passing from its outer side beneath it to its inner side, a key landmark in gland surgery.
What does taste loss on the front of the tongue with normal touch indicate?
A lesion of the chorda tympani or facial nerve (VII), not the lingual nerve.
Educational information, not medical advice. For any symptom, see a health professional.
Its names
- Official Latin (TA2)
- nervus lingualis TA2 6267
- Official Spanish (DeCS)
- Nervio Lingual DeCS D008036
- English (TA2)
- Lingual nerve
Related
Sources: Terminologia Anatomica (TA2); DeCS; Anatomy, Head and Neck, Lingual Nerve.
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.
