Tumor necrosis factor-Alpha stimulates cytokine expression and transient sensitization of trigeminal nociceptive neurons.

Objective: Elevated levels of tumor necrosis factor- alpha (TNF-α) in the capsule of the temporomandibular joint (TMJ) are implicated in the underlying pathology of temporomandibular disorders (TMD). TMD are a group of conditions that result in pain in the TMJ and/or muscles of mastication, and are associated with significant social and economic burdens. The goal of this study was to investigate the effect of elevated TNF-α levels in the TMJ capsule on nocifensive behavioral response to mechanical stimulation of trigeminal neurons and regulation of cytokines within the trigeminal ganglion.