Lingual nerve: sensation of the tongue and floor of the mouth
Quick facts
- Origin
- Branch of the mandibular nerve (V3), the lower division of the trigeminal.
- Function
- General sensation of the anterior two thirds of the tongue, the floor of the mouth and the lingual gum.
- Particularity
- Receives the chorda tympani, a branch of the facial nerve, which carries taste from the same area.
- Close neighbor
- Runs close to the inferior alveolar nerve, before the latter enters the mandible.
The lingual nerve is the branch of the mandibular nerve (V3) responsible for general sensation of the tongue, the floor of the mouth and the gum on the tongue side. It carries touch, pain and temperature. Taste from that same area travels through another nerve, the chorda tympani, which joins the lingual nerve along its course.
Where does it run?
It descends from the deep space of the face, close to the inferior alveolar nerve, and runs between the mandible and the muscles that flank it, such as the mylohyoid, until it reaches the floor of the mouth. For much of its course it lies near the inner surface of the bone, under the mucosa. In clinical language, the closeness between the lingual and the inferior alveolar nerves is the point of greatest interest: what reaches one can reach the other.
| Nerve | Origin | Area |
|---|---|---|
| Lingual | V3 | Tongue, floor of the mouth |
| Inferior alveolar | V3 | Lower teeth, ends as the mental nerve |
| Mental | Continuation of the inferior alveolar | Chin and lower lip |
| Long buccal | V3 | Cheek and buccal gum |
Why does it matter to those who do facial harmonization?
The lingual nerve is not a target for filler or toxin. It shows up in three situations:
- Mandibular anesthetic blocks, common among dentists, which tend to leave the tongue and lip numb at the same time. The patient may complain of difficulty speaking or may bite the tongue without noticing. It is worth explaining this before they leave the office.
- Assessing sensory complaints: numbness in the tongue or floor of the mouth, or altered taste, does not belong to the territory of the chin and lip, which is the mental nerve's. Separating the areas helps locate the problem.
- Differential diagnosis: persistent tingling in the tongue and lower lip, after any oral or mandibular procedure, calls for reassessment and, if needed, referral.
What about taste?
The chorda tympani is a branch of the facial nerve. It joins the lingual nerve and carries taste from the anterior two thirds of the tongue. For that reason, an injury to the lingual nerve can alter sensation and taste together. A patient who reports a "strange taste" after an oral procedure needs to be heard and examined, not reassured right away.
How does it fit into planning?
When the plan includes the jawline or the chin, the professional is already thinking about the mandible and neighboring nerves. The lingual nerve is rarely discussed there, but it belongs to the same V3 innervation map and justifies asking about prior numbness during the medical history.
Also called: lingual, nervus lingualis.
Frequently asked questions
Why can the tongue go numb after anesthesia in the jaw?
The lingual nerve runs next to the inferior alveolar nerve, and an anesthetic block in the area can reach both. The numbness is usually temporary; if it persists, the patient should be reassessed.