Acute experimental dental pain: a technique for evaluating pain modulating procedures.

A simple method for bipolar electrical stimulation of the tooth pulp for evaluating pain modulating procedures is described. Stimulation selectivity has been studied by means of cortical evoked potentials before and after gum anaesthesia. Results obtained by constant current and constant voltage stimulation have been compared. Constant voltage stimulation has proved to be more stable in time. This technique is able to differentiate the analgesic effect of a single dose of i.v. lysine acetylsalicylate from saline. Threshold sensation was judged as painful by about half of the subjects.