Changes in bioelectric potentials on bone associated with direct current stimulation of osteogenesis.

This study was designed to determine whether changes occur in the bioelectric potentials on bone during and after bone stimulation with a 20-microA direct current (DC) and whether the variations in bioelectric potentials are related to the variations in bone formation. The bioelectric potentials were recorded at different times on the rabbit distal tibial surface, during (current-on state) and after (current-off state) DC stimulation with a cathode implanted within the medullary canal. The new bone formed at the end of the experiment was quantitated and related to the bioelectric potentials recorded at current-on and current-off states, respectively. Direct current stimulation resulted in electronegative potential spike centered on the cathode tip while current was applied. After electrical stimulation was turned off, the residual potentials at the end of the experiment did not significantly differ from the initial values. Conversely, the time sequence of the changes was significantly different from the control to the experimental group. The variations in the induced potentials at current-on state were significantly related to the variations in bone formation. This study suggests the existence of a relationship among bioelectric potentials, DC stimulation, and osteogenesis.