The effect of tooth clenching on the sensory and pain perception in the oro-facial region of symptom-free men and women.

ABSTRACT

The aim of this study was (i) to examine the effect of light tooth contact as in diurnal tooth clenching on the tactile detection threshold (TDT), the filament-prick pain detection threshold (FPT) and the pressure pain threshold (PPT) in the oro-facial region and (ii) to examine the possible gender difference in this effect on the tactile and pain perception. Twenty healthy volunteers participated. The TDT and the FPT were measured by means of Semmes-Weinstein monofilaments, on the cheek skin (CS) overlying the masseter muscles (MM) and on the skin overlying the palm side of the thenar skin (TS). The PPT was measured at the central part of the MM using a pressure algometer. Each parameter was measured before and after keeping light tooth contact for 5 min (session 1) and after keeping the jaw relaxed for 5 min (session 2) as a control. Although there were no significant session effects on any of the parameters, there were significant effects of experimental condition on the TDT in both men and women (P < 0.001). Men had a significant higher FPT of the left CS (P < 0.05) and TS (P < 0.01) and a significant higher PPT of the MM than women (P < 0.001). These results illustrate that sensitivity to pain (FPT, PPT) was higher in women than in men. Although there were no significant gender differences in habituation of sensory perception, the increase of TDT after clenching/no clenching was larger in women, which warrants further study.