An Emerging Technique to Kill Drug-Resistant Dental Bacteria: Electrocute Them

By Timothy Hyland

The continued emergence of new strains of drug-resistant bacteria is one of the most challenging issues in the world of health care.

According to the Centers for Disease Control, the United States alone sees more than 2.8 million cases of antibiotic-resistant infections each year. Of those patients, more than 35,000 will die.

Concerted efforts to address the crisis have helped stem the rise of these dangerous bugs. Still, the problem remains a stubborn one, and researchers working across various fields continue their efforts to develop new means of winning the war against drug-resistant bacteria—including in the field of dentistry.

Newly published research from a team at the University of Pittsburgh, for instance, has revealed a potentially innovative new way to battle drug-resistant bacteria and potentially dangerous infections in the mouth.

Tago Niepa, PhD — *Tagbo H.R. Niepa, PhD*

The team set out to address a persistent problem related to titanium-based dental implants: their susceptibility to infection.

Though titanium is in many ways a perfect material for these implants, the Pitt research team also notes it has one major downfall: specifically, the surface of titanium makes an incredibly comfortable home for any number of microbes.

This colonization, when left unchecked, will occasionally cause inflammation and infection of the surrounding tissues, and as other recent research has shown, it can ultimately cause damage to the titanium itself. In fact, some studies indicate that up to 10 percent of all titanium implants will fail within 10-15 years.

While the shocks delivered by the ECT do negatively impact the microbes, they leave teeth and gums unscathed.

Though these infections can often be treated with antibiotics, sometimes the drugs simply don’t work, leaving the dentist with limited options. Thanks to the work of the team at Pitt, however, that may not be the case much longer.

Led by Tagbo H.R. Niepa, PhD, an assistant professor of chemical and petroleum engineering at Pitt’s Swanson School of Engineering, the group explored the use of electrochemical therapy (ECT) to address these oral infections, and the results have been promising.

By first treating the area with ECT, the team found that otherwise untreatable bacteria are destabilized and weakened, making them more susceptible to antibiotic treatment than they may have been otherwise.

Dr. Niepa and his team developed and tested a “one-two punch” approach to the problem of stubborn microbes in the mouth. By first treating the area with ECT, the team found that otherwise untreatable bacteria are destabilized and weakened, making them more susceptible to antibiotic treatment than they may have been otherwise. While the shocks delivered by the ECT do negatively impact the microbes, they leave teeth and gums unscathed.

The research was conducted specifically to test the technique on the common bacteria Candida Albicans, which is the root cause of oral thrush, yeast infections, and urinary tract infections.

In their paper, published in the journal ACS Applied Materials and Interfaces, the team said it had “demonstrated that the electrochemically induced sensitization of C. albicans followed by treatment with an antifungal agent is a promising approach to eradicate drug-tolerant species.”

Dr. Niepa, in a statement issued through Pitt, added: "With this technique, the current doesn't discriminate as it damages the microbe cell membrane. It's more likely that antibiotics will be more effective if the cells are simultaneously challenged by the permeabilizing effects of the currents. This would allow even drug-resistant cells to become susceptible to treatment and be eradicated."

The novel method passes a weak electrical current through the metal-based implant, damaging the attached microbe's cell membrane but not harming the surrounding healthy tissue. This damage increases permeability, making the microbe more susceptible to antibiotics. Since most antibiotics specifically work on cells that are going to replicate, they do not work on dormant microbes, which is how infections can recur. The ECT causes electrochemical stress in all the cells to sensitize them, making them more susceptible to antibiotics.

While dental implants are one exciting application for this new technology, Dr. Niepa says it has other potential applications, such as in wound dressings. The researchers hope this technology will change how infections are treated.

Author: Contributing writer Timothy Hyland has more than 20 years' experience as a writer, reporter, and editor. His work has also appeared in Fast Company, Roll Call, Philadelphia Business Journal, and The Washington Times.

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