Animal Models for Orofacial Neuropathic Pain

Abstract

Orofacial neuropathic pain is initiated by extraction of teeth or nerve injury from trauma in the trigeminal nerve that innervates the facial area. In the experiment, orofacial neuropathic pain usually occurred following injury of peripheral trigeminal nerve including infra-orbital nerve, inferior alveolar nerve, or mental nerve. In addition, pathology from trigeminal nerve root or ganglion is involved in orofacial neuropathic pain. This study introduced various animal models that help us study the underlying mechanisms of development or maintenance of orofacial neuropathic pain. One of the most typical symptoms of orofacial neuropathic pain is hypersensitivity to the innocuous mechanical stimuli. Our study presents a novel method to evaluate mechanical allodynia in rats with orofacial neuropathic pain. Recently, accumulate evidence support participation of central glial cells in the development or maintenance of orofacial neuropathic pain. Signaling molecules in glial cells also play an important role in neuropathic pain in the orofacial area.