Table 2.

Difference between nociceptive, inflammatory, and neuropathic pain

CharacteristicsNociceptive orofacial painInflammatory orofacial painNeuropathic pain
Causes and mechanism of pain pathwayNoxious stimulation at the peripheral nerve and transmitted by normal components of the sensory trigeminal nerveStrong noxious stimulus causes lesions in the tissue leading to local inflammation responses and increased inflammatory mediatorsCaused by nerve damage or injury and increased peripheral sensitization, structure change by increased sodium activation, calcium activity of nerves leading to ectopic discharges, and glia cell activation
Nerve conditionNormal nerve structureNormal nerve structureAbnormal nerve structure
StimulationResponse to noxious stimulus for protective and withdrawal responseResponse to noxious stimulus and increase of activity of peripheral nociceptors-Response to non-noxious and noxious stimulation
-Spontaneous pain without stimulation because ectopic discharges occurred in damaged nerves
ExampleHot soup contacting the oral mucosa immediately caused pain perception (heat/hot), and then they threw away this hot soup-Pulp necrosis with apical abscess
-Temporomandibular joint capsulitis or synovitis is caused by joint inflammation. Joint pain and limitation of jaw movement develops afterward
Peripheral trigeminal nerve injury is caused by nerve damage such as facial trauma accident or trigeminal neuralgia contributing to abnormal nerve structure and expression of severe shooting pain, intermittent patterns, and feels like electric shocks