The measurement and research of surface potentials of human tooth in vitro

Previous studies have shown that there are surface potentials in the separate tooth sections and a whole tooth in vivo. To confirm the existence of the surface potentials in extracted tooth and research the development of the potentials, the surface potentials between mid-spots of enamel crown´s buccal side and tooth root were measured with electrochemical methods. The effects of KCl concentration and acid corrosion were also examined in the present study. All the teeth developed the surface potentials, and when 0.1 mol/L KCl solution was used, the average surface potential was +20.83 ± 11.47mV. The potentials increased along with the ascending of KCl concentration and after being acid corroded. The results of this study suggested that there are also surface potentials in tooth as a whole tissue in vitro, and the potentials can be affected by the electrolyte surroundings and are developed mostly by the dental crystal structure and established in the outer layer, an electric double layer.