Analysis of the electrolytes’ pH before and after electrolysis

As shown in Table 1, pH of electrolyte (catholyte) was not changed after electrolysis of different currents. However, the pH decreased after electrolysis of anodic potential of 1 A and 1.5 A in group I and II.

Evaluation of the amount of stained area (contamination) of the healing abutments

The percentage of residual contaminated area of the healing abutments after electrochemical treatments with 0.5 A showed no significant differences between cathodic and anodic potential in group I, II, and III (Fig. 1). However, significant differences were seen between cathodic and anodic potential of 1 A and 1.5 A in both group I (P < 0.05) and group III (P < 0.01). In group I, electrochemical treatments with 1 A and 1.5 A in cathodic potential showed 11% and 12% of residual contamination, respectively. Electrochemical treatments in group II showed no significant differences in the percentage of residual contamination between 1 A and 1.5 A in cathodic and anodic potential. Although the use of 1 A and 1.5 A was more effective than 0.5 A in both cathodic and anodic potential, complete decontamination was not achieved. Among three groups, applying 1 A in cathodic potential in group III resulted in the lowest percentage of residual contamination on the healing abutments compared with group I (P < 0.05) and group II (P < 0.01). In addition, the percentage of residual contamination after applying 1.5 A in cathodic potential in group III also resulted in significantly lower than that in group I (P < 0.05) and group II (P < 0.01).

After applying 1 A and 1.5 A in cathodic potential in group III, the percentage of residual contamination was 1% and 2%, respectively. Microscopic views of a healing abutment stained with phloxine B after cleaning with different electrolytic cleaning treatments were shown in Fig. 2.