Variations in the anatomy of the auriculotemporal nerve.

The common representation of the auriculotemporal nerve is either that of a single posterior branch of the mandibular nerve or of two roots that envelope the middle meningeal artery. Our observation in the anatomy of the auriculotemporal nerve on 32 dissections (16 cadaveric heads) of the infratemporal fossa included: one specimen with four roots (3.1%), three specimens with three roots (9.4%), 12 specimens with two roots (37.5%), and 16 specimens with one root (50%). Furthermore, a connecting nerve branch was observed between auriculotemporal and inferior alveolar nerves in four specimens, and in another auriculotemporal nerve case, between the upper and lower roots. In the cadaver of a 70-year-old male, a four-rooted auriculotemporal nerve variation was found. These four branches lay to the posterior, combined at the posterosuperior of the maxillary and superficial temporal arteries and formed a ganglion-like knot. From this knot, four branches stemmed and ran to the temporomandibular joint, external acoustic meatus, zygoma, and parotid gland. The knot was larger and thicker than expected; thus, it was removed and stained with haematoxylin-eosin (H&E) and S100 for histological studies. This structure was not a true ganglion but a structure formed by fusion of nerve fibers.