[Effect of high-frequency percutaneous stimulation on experimental pain].

Ten healthy volunteers were submitted to an experimental pain test performed by electrical stimulation of one tooth, before and after 20 min high-frequency (300 Hz) electrical stimulation, for the purpose of relieving pain, delivered to the lip or to three other somatotopically non related areas. The stimulation of the lip only showed a statistically significant analgesic action. The effect was remarkable (31% of total pain relief) and of the same order of magnitude at any intensity level of the tooth stimulation, the threshold being affected too. It is concluded that a central inhibitory mechanism, activated by large afferents input, should subserve this kind of analgetic procedure.