Reduced thermal threshold in patients with Temporomandibular Disorders

Summary Background Many studies have demonstrated the presence of somatosensory modulation changes at different sites in patients with temporomandibular disorders ( TMD s) using different modalities. However, the neck area, a well‐know condition related to TMD , remains unexplored. Objective To assess the thermal pain threshold in patients with TMD and controls at cephalic and extra‐cephalic areas, including the neck. Methods Twenty female patients with TMD s diagnosed by the Research Diagnostic Criteria for TMD ( RDC / TMD ) and twenty age‐matched controls underwent a first interview about neck pain and disability ( NDI questionnaire). A blinded evaluator assessed the thermal pain threshold for cold ( CPT ) and heat ( HPT ) stimuli in accordance with an ascending method of limits of the Quantitative Sensory Testing at the following sites: periorbital, masseter, cervical posterior and ventral forearm. The groups were compared using a t ‐test with α = 5%. Results Patients with TMD s reported pain at higher temperature for cold stimuli in all sites ( P < 0·05) and at lower temperature for heat stimuli in the right periorbital site ( P < 0·05) than controls. Pain and disability due tothis symptom were reported more often in the TMD group ( P < 0·05). Conclusion Patients with TMD have pain modulation changes in the neck area as well, especially for cold stimuli, associated with higher disability and a higher report of neck pain than controls. These findings reinforce the evidence regarding the relationship between TMD s and neck pain.