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Updated: Jun 28, 2026

Using Flexible Gold-Titanium Reaction Cells to Simulate Pressure-Dependent Microbial Activity in the Context of Subsurface Biomining
Published on: October 5, 2019
Effect of surface area ratios and bacteria on electrochemical behavior of galvanically coupled titanium
Ilwoong Koh1, Yoshiki Oshida, Carl J Andres
1Department of Biologic and Materials Sciences, Division of Prosthodontics, University of Michigan School of Dentistry, Ann Arbor, Michigan 48109-1078, USA. ilwoong@umich.edu
Purpose:
This study aimed to investigate the electrochemical behavior of commercially pure titanium (grade II) coupled with type IV gold alloy and nickel-chromium alloy at different surface area ratios in 3 different electrolytes.
Materials And Methods:
Titanium was coupled with gold (Ti/Au) and nickel-chromium (Ti/Ni-Cr). For each couple, 9 surface area ratios between titanium and gold or nickel-chromium were prepared. The electrolytes used were 1% lactic acid, tryptic soy broth media, and Streptococcus mutans culture supernatant. The corrosion polarization curves were obtained, and average values of corrosion potential and corrosion current density were calculated.
Results:
Both Ti/Au and Ti/Ni-Cr were affected by surface area ratios and different electrolytes, showing the least corrosion rate when the ratio was 1:1 and when the lactic acid was used as an electrolyte.
Conclusions:
The greater the difference in surface area between titanium and restorative materials, the more corrosive behavior the materials show. The existence of bacteria such as S mutans may aggravate corrosive behavior between different metals.
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