Orofacial pain and sensory characteristics of chronic patients compared with controls.

OBJECTIVES: To investigate orofacial and sensorial characteristics of patients with orofacial pain and healthy controls. STUDY
DESIGN: Case-control. Seventy-five patients (61 women) who had chronic orofacial pain for more than 6 months (i.e., idiopathic trigeminal neuralgia, burning mouth syndrome, persistent idiopathic facial pain, nonidiopathic neuropathic pain, fibromyalgia or temporomandibular disorders were compared with 41 healthy subjects (19 women). They were evaluated with a quantitative sensory testing protocol involving a combination of gustative, olfactory, thermal, mechanical and pain stimuli. Mean pain duration in this population was 6.27 ± 6.06 years. Orofacial characteristics (masticatory and articular abnormalities), oral health and sensitivity to muscular palpation were assessed.
RESULTS: The majority of patients (73.3%) had pain upon craniofacial muscle palpation and 46.7% had numbness. High cold thresholds were observed with burning mouth syndrome and nonidiopathic neuropathic pain (P = .017), while high tactile thresholds were observed in persistent idiopathic facial pain patients (P = .048). Persistent idiopathic facial pain and temporomandibular disorders were associated with a low threshold for pain perception (P < .002). Several of these sensorial alterations were associated with positive musculoskeletal findings.
CONCLUSIONS: Sensorial abnormalities were observed in neuropathic and somatic pain patients. The masticatory system is associated with and may be a secondary cause of pain in such patients.