The activation of opioid receptors by exogenous or endogenous opioids can produce
significant analgesic effects in peripheral tissues. Numerous researchers have demonstrated
the expression of peripheral opioid receptors (PORs) and endogenous opioid peptides
(EOPs) in the orofacial region. Growing evidence has shown the involvement of PORs
and immune cell-derived EOPs in the modulation of orofacial pain. In this review,
we discuss the role of PORs and EOPs in orofacial pain and the possible cellular mechanisms
involved. Furthermore, the potential development of therapeutic strategies for orofacial
pain is also summarized.