The effect of electrical potential on the penetration of metal ions through radicular dentin.

PURPOSE Electrical potential may facilitate the moving of corroded metal ions across radicular dentin to cause allergic reaction. This study was to investigate the effect of electrical potentials on the penetration of silver and copper ions through radicular dentin. MATERIALS AND METHODS Eighty-eight dentin discs were prepared from intact premolar teeth and placed between two containers of the model. One container was filled with copper and/or silver solution. Another container was filled with 0.9% sodium chloride solution. Five levels of electrical potential were applied to the model at 37 degrees C for 1 and 24 hrs. Then silver and copper ions in sodium chloride solution were measured by ICP-ES. The data was analyzed by one-way ANOVA with Tukey comparison test and student's t-test (P< 0.05). RESULTS The concentrations of metal ions significantly increased as the electrical potentials increased when above 250 mV were applied after 1 hr. The concentrations of silver ions were significantly greater than those of copper ions. Low concentrations of silver and copper ions were detected after 24 hrs at 125 mV level. CONCLUSIONS These results suggest that the penetration of corroded silver and copper ions through radicular dentin caused by intraoral potential might be minimal.