Irradiation of pain

Pain irradiation (Latin: dolor irradians) is the process of pain impulse spreading from the focus of inflammation to other areas innervated by nerve branches. In dentistry, this phenomenon is most often observed in irreversible pulpitis.

Etiology and pathophysiology

The mechanism of development is related to convergence (convergence) of nerve pathways. Pain signals from different teeth and areas of the face are transmitted to the common trigeminal nuclei in the brain. Under intense irritation, the brain loses the ability to localize the exact source, and the patient feels as if the pain is coming from a healthy tooth, ear, temple, or the entire half of the jaw.

Clinical significance

Irradiation of pain is a classic sign of irreversible pulpitis and an important criterion for distinguishing it from apical periodontitis. When the infection passes beyond the root into the ligamentous apparatus of the tooth, the irradiation usually disappears and the pain becomes clearly localized, which makes it possible to identify the causative tooth.