Morphology of the auriculotemporal nerve and its relationship with temporomandibular joint

The auriculotemporal nerve located in the infratemporal fossa provides sensory innervation of the tragus, part of auricle and posterior part of the temporal region. Also, it is an important structure that carries the parasympathetic fibers of the glossopharyngeal nerve. Neuralgia, which is characterized by penetrating pain mostly over the temporal region, occurs in the form of seizures in cases where this nerve, which is in close relationship with the maxillar and middle meningeal arteries, is traumatized or compressed throughout its course, it has been reported that neuropathy may develop after mechanical compression on the temporamandibular joint due to its location. However, there is an insufficient evidence regarding the morphometry of the nerve as a whole, its formation pattern, its position with the surrounding vascular structures and temporamandibular joint. In this study, it was aimed to reveal the relationship between auriculotemporal nerve morphometry, branching pattern, position with vascular structures and temporamandibular joint in both adult cadavers and fetuses. In our study, bilateral infratemporal fossa dissections were performed on 15 adult cadavers (mean age 76,07 ± 14,1 years) and 15 fetuses (23,87 ± 3,40 weeks). The auriculotemporal nerve and number of roots forming itself, morphometry, formation pattern, relation with vascular structures and localization according to articulatio temporomandibularis were recorded. Typing was also done according to the relationship of the nerve with the middle meningeal and maxillar arteries and the connection configuration between the roots. It was determined that the auriculotemporal nerve detected in both adult cadavers and fetuses exhibited various combinations of roots and connections. While the number of roots forming the auriculotemporal nerve was at most 5 in adult cadavers, it was at most 4 in fetuses. While the number of roots forming the auriculotemporalis was at most 5 in adult cadavers, it was at most 4 in fetuses. It was recorded that the frequency of 2 roots observed for both materials was 60%. One of our findings was that in 87% of adult cadavers and in 90% of fetuses, the first root was lateral to the middle meningeal artery, and the second root was medial to the artery in 81% and 79%, respectively. When the relationship between auriculotemporal nerve and the joint is evaluated; It was determined that the distance from the point where the nerve intersects with the anterior edge of the collum mandible to the sagittal axis passing through the midpoint of the lower edge of the arcus zygomaticus is 3,542 mm more in men than in women. In addition, the mean distances of the nerve to the sagittal and vertikal axes passing through the anterior and posterior margins of the neck of mandible and zygomatic arch and intertragic incisure were found to be 10.36 mm, 13.76 mm, 26.65 mm and 15.37 mm, respectively. As a result, a good understanding of the characteristic structure of the nerve is required for applications to be performed in the this region with a complex anatomy. Illumination of this diversity, especially with dissection studies, will contribute to invasive procedures in the region.