Laroussi's Cold Plasma Research Highlighted by Australian Broadcasting Corp.

Old Dominion University electrical and computer engineering professor Mounir Laroussi has been highlighted in an article by the online news service of the Australian Broadcasting Corp. (ABC).

The story, published June 24, mentions the research of University of Southern California professor Chunqi Jiang. An article by Jiang and colleagues in the upcoming journal Plasma Processes and Polymers mentions research at USC that may lead to the development of a plasma "torch," a tool that would make dental procedures easier, less painful and reduce the chance of infection.

"Our goal is to guarantee that you won't have to see a doctor for a follow-up visit," Jiang told ABC.

The article goes on to quote Laroussi at length, identifying him as one who has studied the effects of cold plasmas for years.

Laroussi told ABC that the trick to creating plasma at room temperature is to pulse it. A continuous stream of plasma very quickly heats up the surrounding air. Pulsing allows the tiny electrons in the plasma to heat up and move around, while keeping the much larger and heavier atom nucleus from heating up.

"If you have a piece of paper with bacteria on it and you apply cold plasma to it, the paper won't burn but the bacteria will die," Laroussi told ABC.

"Cold plasma can kill bacteria on a variety of surfaces such as teeth or skin."

Tests using cool, pulsed plasma have shown its ability to kill biofilm material on teeth and gums, without harming the surrounding tissue and showing no signs of infection.

ABC reported that other high-tech solutions to biofilms have existed for a decade, but the problem is cost. Laser systems can also clear away biofilms, but are expensive, costing up to $25,000.

In 2005, Laroussi developed a cold plasma torch, costing less than $1,000, which he has used to test the effects of cold plasma on teeth, skin and wounds.

"We can kill bacteria on teeth and on wounds," said Laroussi. "But we have to ensure that we are not creating a worse problem in nearby healthy cells as well."

Laroussi is currently conducting research in this area with Professor Michele Darby and Associate Professor Gayle McCombs in ODU's School of Dental Hygiene.