Temporomandibular joint innervation: Anatomical study and clinical implications

Temporomandibular disorders and related pain are commonly seen in clinical practice. They seriously affect social life since they are mostly recurrent. Current knowledge concerning temporomandibular joint (TMJ) innervation is unclear and is insufficient to perform the appropriate treatments for the underlying pathophysiology in these patients. The aim of our study is to elucidate the pathophysiology of orofacial pain of temporomandibular origin by revealing the TMJ innervation topography, its variations and its relationship with surrounding anatomical structures. This will help us create a guide for treatment interventions to be planned in the light of these data. A total of 20 cadaver half-heads, 10 fresh frozen and 10 embalmed, were dissected. TMJ nerves were dissected together with the associated surrounding anatomic structures. TMJ innervation topography and variations were demonstrated. We showed that TMJ is mainly innervated by the auriculotemporal nerve posteriorly, as well as the masseteric nerve anteriorly, the posterior deep temporal nerve anteromedially, and by a TMJ branch coming directly from the mandibular nerve medially and their frequency with several variations. In addition, we emphasized how these nerves might be affected in certain clinical conditions based on anatomical relationships and pathophysiological mechanisms. To our knowledge, this is the first study in the literature to show the existence of a branch of the mandibular nerve that directly innervates TMJ. In the light of our findings, explaining TMJ pain based on anatomical characteristics of the region will result in precise treatment algorithms and better clinical outcomes in the management of these disorders. Based on this study, new clinical studies and interventions can be designed to reduce the healthcare costs and to alleviate the burden of TMJ pains in these patients.