Neurobiological Links Between Endodontic Pain and Temporomandibular Disorders: A Comprehensive Review.

Endodontic (pulpal and periapical) pain and temporomandibular disorders (TMDs) are often considered to be clinical entities in different dental subspecialties. Both are present in the same sensory system (the trigeminal nerve and its central projections); however, there is recent evidence to suggest that some common neurobiological substrates exist between the two. Mechanistic connections between the inflamed/instrumented tooth and the masticatory muscle and joint pain associated with TMD consist of peripheral sensitization at the inflamed/instrumented tooth, activity-dependent changes in trigeminal ganglion neurons, and activity-dependent changes in the trigemino-thalamo-cortical axis. The current review is an overview of recent literature (2020-2026) that underscores the common neuroanatomy, transition of acute nociceptive endodontic pain to sensitized and even neuropathic states, and clinical overlap in these conditions for persistent dentoalveolar pain and post-traumatic trigeminal neuropathy. This knowledge is directly relevant to diagnosis, to avoiding iatrogenic roll-down, and to management strategies that intervene in sensitised central pathways and not just in the tooth. We believe that an understanding of endodontic pain and TMD should be considered a continuum of trigeminal nociceptive and neuroplastic processes.