The 5 peripheral branches of the facial nerve are branches that extend outward from the main nerve trunk to control muscles of facial expression. According to the traditional description, these include the temporal, zygomatic, buccal, marginal mandibular, and cervical branches. However, keep in mind that there can be significant variability in how these branches divide and connect.
The Five Main Peripheral Branches of the Facial Nerve
Here's a breakdown of each of the 5 main peripheral branches:
| Branch | Target Muscles | Function |
|---|---|---|
| Temporal | Frontalis (forehead), orbicularis oculi (eye), corrugator supercilii (eyebrow) | Controls forehead movement (raising eyebrows, wrinkling forehead), closes the eye, and draws the eyebrow medially. |
| Zygomatic | Orbicularis oculi (eye), zygomaticus major and minor (cheek) | Closes the eye tightly and elevates the corners of the mouth (smiling). |
| Buccal | Buccinator (cheek), orbicularis oris (mouth), muscles of the upper lip | Compresses the cheek (as in whistling), closes the mouth, and controls movements of the upper lip (e.g., smiling, pursing lips). |
| Marginal Mandibular | Depressor anguli oris (lower lip), depressor labii inferioris (lower lip), mentalis (chin) | Depresses the corner of the mouth (frowning), depresses the lower lip, and wrinkles the chin. |
| Cervical | Platysma (neck) | Tenses the skin of the neck and helps depress the mandible. |
Branching Variability
It is important to remember that the branching pattern of the facial nerve can vary considerably between individuals beyond the pes anserinus. This is the point where the facial nerve divides within the parotid gland. This means that the specific distribution and function of these branches may not always be exactly as described in textbooks.
