While the facial nerve (CN VII) has five main branches—temporal, zygomatic, buccal, mandibular, and cervical—it's less common to refer to them as three divisions. The sources provided don't consistently support a three-division categorization. The branches are more accurately described as a series of five distinct branches arising from a single nerve. However, grouping these five branches could be interpreted in different ways. One possible interpretation for grouping them into three might be:
- Superior Division: This would encompass the temporal and zygomatic branches, both responsible for innervating the upper face muscles.
- Middle Division: This would include the buccal branch, responsible for innervating the cheek muscles.
- Inferior Division: This comprises the mandibular and cervical branches, innervating muscles of the lower face and neck, respectively.
It is important to note that this three-division grouping is not a standard anatomical classification, and the five-branch description is far more prevalent and precise in anatomical literature.
The five branches, in order from superior to inferior, are:
- Temporal branch: Innervates the muscles of the forehead and the muscles around the eye.
- Zygomatic branch: Innervates the muscles of the cheek and upper lip.
- Buccal branch: Innervates the muscles of the cheek.
- Marginal mandibular branch: Innervates the muscles of the lower lip and chin.
- Cervical branch: Innervates the platysma muscle in the neck.
These branches are responsible for controlling facial expressions and are crucial for normal facial function. Damage to the facial nerve or its branches can result in facial paralysis.
