Does acute intraoral pain alter cutaneous sensibility?

Cutaneous sensibility was tested in eight patients suffering from acute postoperative intraoral pain. Tactile-, cold-, warm-, and heat-pain thresholds as well as reaction time to cold pulses were unaffected by the presence of pain. However, reaction time to warm pulses was increased in the painful area on the day of pain compared to a non-painful state. The findings are discussed in relation to (1) functional convergence of different sensory fibres on central neurons (2) the phenomenon of diffuse noxious inhibitory controls and (3) secondary hyperalgesia. The observed effect of clinical pain on the warm pathway could be explained as an intrasegmental noxious inhibitory effect.