[Electrical pain thresholds of face and finger in patients with chronic masticatory muscle pain]

Abstract

Objective: To compare electrical sensory threshold (EST) and electrical pain threshold (EPT) of bilateral masseters, temporal muscles and finger region of chronic masticatory muscle pain (MMP) patients and the controls, and to analyze the mechanism of pain threshold change.

Methods: Twelve patients with MMP and 12 matched controls participated in this study. EST and EPT of bilateral masseters, bilateral temporal muscles, and left middle finger were recorded and compared within group and between groups.

Results: Compared to the controls, the EPTs of patients significantly decreased [left masseter (5.9 +/- 1.1) mA,right masseter (5.7 +/- 1.0) mA, left temporal muscle (5.3 +/- 1.4) mA, right temporal muscle (5.5 +/- 1.7) mA,finger (5.2 +/- 1.0) mA] (P < 0.001). There was no significant difference in EST between patients and the controls. No relationship was found among VAS, ESP, and EPT.

Conclusions: Decreased pain thresholds of masseters, temporal muscles and fingers in MMP indicated that peripheral sensitization was induced in MMP patients. Decreased pain threshold in patients meant that MMP might influence the central modulation of nervous system.