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Updated: Apr 25, 2026

Assessment of Nerve Injury-Induced Mechanical Hypersensitivity in Rats Using an Orofacial Operant Pain Assay
Published on: July 26, 2022
Somatosensory investigation of patients with orofacial pain compared with controls
Silvia R D T de Siqueira1, Manoel J Teixeira1, Jose T T de Siqueira1
1From the School of Arts, Science and Humanities (SRDTdS); Neurology Department, School of Medicine (MJT); and Dentistry Division, Hospital das Clinicas, School of Medicine (JTTdS), University of Sao Paulo, Sao Paulo, Brazil.
Abstract:
The objective of this study was to investigate the sensorial characteristics of orofacial pain in patients compared with control subjects. A total of 336 subjects (282 patients and 54 control subjects) were evaluated to identify their thermal (cold and warm), tactile, and pain thresholds. Numbness was reported by 61.7% of the patients (p<0.001). Patients with trigeminal postherpetic neuralgia and burning mouth syndrome showed loss of thermal perception; patients with postherpetic neuralgia, burning mouth syndrome, and posttraumatic painful neuropathy had a decrease in tactile perception compared with the control subjects (p<0.001). In conclusion, other sensorial modalities besides pain are affected by neuropathic orofacial pain; these findings can help in the understanding of the pathophysiological mechanisms in orofacial pain.

