Mandibular Nerve and Maxillary Artery Anatomical Variations: Implications for Dentistry, Maxillofacial and Oral Surgery

Abstract

BACKGROUNDThe posterior division mandibular nerve (V3) gives rise to several branches in the infratemporal region, including the auriculotemporal (ATN), lingual (LN), and inferior alveolar (IAN) nerve. The IAN block is the most commonly performed local anesthetic technique used in dentistry, and atypical morphology of the IAN could lead to block failure or complications. Further, all of the V3 branches are located in close proximity to the maxillary artery, the main blood supply to the maxillofacial region, thus need to be considered and avoided during surgery.OBJECTIVEHere we present a case series derived from examination of n=12 cadavers as part of routine dissection in a gross anatomy course. We examined the infratemporal fossa of each cadaver for V3 and maxillary artery anatomical variations.RESULTSVariations in either V3 or the maxillary artery were clearly visible in 3 out of 12 cadavers. The potential clinical significance of two selected variations is summarized here: Variant 1: Just inferior to the origin of the IAN and LN from V3, we observed IAN fenestration around the second part of the maxillary artery. This variant is clinically relevant from multiple standpoints, as the position of the artery is unexpected, and therefore may be unintentionally compromised. Variant 2: Just inferior to the origin of the IAN and LN from V3, we observed an anomalous communicating branch between the IAN and LN. While we cannot ascertain the functional significance or origin of this branch, this coalescence of nerve fibers may limit the ability to “target” the nerves individually. For example, IAN block may also affect LN fibers, leading to alterations in taste and tongue sensation. CONCLUSIONVariations in the branching of V3 or maxillary artery were clearly visible in 3/12 cadavers. As such, variations were found in 25 percent of specimens; however, several of the specimens were damaged during dissection, thus the true incidence of variations could likely be higher. Further, these variations may be more common in patients than expected and need to be carefully considered in surgical procedures. Lastly, several variations described here have been previously described in the literature, thus the incidence of these specific variants may be much higher than expected.Support or Funding InformationN/AThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.