Trigeminal Central Sensitization and Its Modulation in Acute and Chronic Orofacial Pain Models

This study aimed to examine whether trigeminal nerve injury induces chronic nociceptive behaviour and central sensitization (CS) in functionally identified medullary dorsal horn (MDH) nociceptive neurons in mice, and whether CS in acute and chronic orofacial pain models and nociceptive behaviour in the chronic model are affected by systemic administration of pregabalin. Infraorbital nerve injury induced chronic facial mechanical allodynia as well as MDH CS; acute noxious tooth pulp stimulation also induced MDS CS. Systemic administration of pregabalin attenuated the nerve injury-induced allodynia as well as the MDH CS in both the chronic and acute pain models. These findings reveal that MDH CS occurs in mouse models of acute and chronic orofacial pain and that pregabalin may prove useful clinically in acute and chronic orofacial pain states.