According to the previous studies, complete killing of bacteria was seen at anode with low current. However, in this study, complete removal of contaminant was seen in electrolysis after cathodic potential 1 A and 1.5 A in group III. This complete removing action can be attributed to the alkaline environment generated at cathodic potential. Moreover, decrease in electrolytes’ pH after electrolysis with anodic potential 1 A and 1.5 A in group II was seen. This could be attributed to the surface destructive process and influence the biocompatibility of commercially pure titanium and titanium alloy surface.

The use of an electric current more than 1100 mA has a potential to alter the titanium surface. Cathodic potentials can generate electro-repulsive forces between the negatively charged surface and bacteria, resulting in their detachment. It can also induce water electrolysis that produce hydrogen gas and increased pH (alkaline) as stated above. The alkaline pH has bactericidal effects mainly through hydrolysis of the bacterial polysaccharide matrix, whereas the generated H₂ gas bubbles adjuncts the detachment of surface contaminants and bacteria. Therefore, cathodic potential 1 A in group III did not result in a significantly greater surface roughness compared to the control suggesting that there was no visible surface alternation on the surfaces. Although using cathodic potential 1.5 A in group III can also be removed the contamination completely, significantly higher surface roughness compared to other groups was seen. However, the subjective nature of the scoring method could potentially influence these results. The findings in this study showed that in spite of some of the differences in surface changes of dental implant healing abutments caused by electrolysis, there were no significant differences between that cathodic potential 1 A and 1.5 A in group III in the percentage of residual contamination.