Inhibitory Effect of Acid Electrolyzed Water on Plaque Formation

The purpose of this study was to evaluate the inhibitory effect of acid electrolyzed water on plaque formation. Seven healthy subjects participated in this study. Before the experiment, the Gingival Index (GI) of all teeth and Gingival Crevicular Fluid (GCF) units of the upper canines were examined, and all teeth were cleaned with an air polisher and hand scaler. The subjects were asked to stop their own daily oral hygiene procedures for 4 days and to rinse with 150 ml of acid electrolyzed water 4 times daily, one minute each time. Two and 4 days later, supragingival plaque was collected from the upper 1st or 2nd premolars and colony forming unit (CFU) were assayed. After 4 days, GI, GCF units, and Plaque Index (PH) were recorded. Povidone iodine solution and physiological saline were used as positive and negative controls, respectively. GI was significantly lower in the acid electrolyzed water group than in the physiological saline group. PlI in the acid electrolyzed water group was the same as in the physiological saline group, and significantly higher than in the povidone iodine solution group. There were no significant differences in GCF units among the three groups. After 2 days, CFU in the acid electrolyzed water group was significantly lower than in the physiological saline group, and the same as in the povidone iodine solution group. However, no significant improvements were observed after 4 days. These results suggested that both acid electrolyzed water and povidone iodine solution had bactericidal activity after 2 days, but were no longer effective after 4 days, and that acid electrolyzed water was not as effective as povidone iodine solution for plaque inhibition after 4 days.