Effect of non-functional tooth contact on tactile and pain thresholds

“Objectives:” The aim of this study was to evaluate the tactile detection threshold (TDT), the tactile pain detection threshold (TPDT), and the pressure pain threshold (PPT) in the orofacial region, before and after keeping light tooth contact as in diurnal tooth clenching.

“Methods:” Thirteen healthy volunteers (5 males, 8 females, age range 26 to 42 years) participated. Using a stair-case method, the TDT and the TPDT were measured by means of Semmes-Weinstein monofilaments, on the cheek skin overlying the masseter muscles (MM). The PPT was measured at the central part of the MM using a pressure algometer. The pain intensity during the measurement of TDT, TPDT and PPT was assessed on a numeric rating scale (NRS). Each parameter was measured before and after keeping light tooth contact for 5 minutes.

“Results:” In males, there was no significant effect of tooth contact on any of the parameters. By contrast, in females, TDT significantly increased from before to after keeping tooth contact (paired t-test: p < 0.05). No changes were observed regarding the TPDT, PPT and NRS.

“Conclusion:” In females, TDT seems to be influenced by a condition mimicking diurnal clenching. Whether this difference directly results from the clenching exercise or from habituation to the experimental situation, needs to be addressed in future controlled studies, also including sufficient numbers of participants.