Biofilm No Match for New Plasma Tool
Biofilm No Match for New Plasma ToolAs part of a collaborative effort, USC School of Dentistry and Viterbi School of Engineering researchers have developed a small probe that produces a pencil sized plume of room temperature plasma that safely fights
Biofilm No Match for New Plasma Tool
As part of a collaborative effort, USC School of Dentistry and Viterbi School of Engineering researchers have developed a small probe that produces a pencil-sized plume of room-temperature plasma that safely fights tenacious biofilm infections.
Chunqi Jiang, a research assistant professor in the Ming Hsieh Department of Electrical Engineering-Electrophysics, and Parish Sedghizadeh, assistant professor of clinical dentistry and Director of the USC Center for Biofilms, report their findings about the device in the article “Nanosecond Pulsed Plasma Dental Probe,” in the June 2009 issue of Plasma Processes and Polymers.
The study reports that biofilms cultivated in the root canal of extracted human teeth were easily destroyed with the plasma dental probe, evidenced by scanning electron microscope images of near-pristine tooth surfaces after plasma treatment.
While many natural plasmas are hot, or thermal, the probe developed for the study uses non-thermal, room temperature plasma that is safe to touch. Jiang explains that researchers placed temperature sensors on the extracted teeth before treatment and found the temperature of the tooth increased just five degrees after 10 minutes of exposure to the plasma.
The cooler nature of the experimental plasma originates from its pulsed power supply. Instead of employing a steady stream of energy to the probe, the pulsed power supply sends 100-nanosecond pulses of several kilovolts to the probe once every millisecond, with an average power less than 2 watts, Jiang says.
“Atomic oxygen [a single atom of oxygen, instead of the more common O2 molecule] appears to be the antibacterial agent,” according to plasma emission spectroscopy obtained during the experiments, Jiang adds.
Sedghizadeh says the oxygen free radicals might be disrupting the cellular membranes of the biofilms to cause their demise, and that the plasma plume’s adjustable, fluid reach allows the disinfection to occur in areas of the root canal most difficult to reach.
Given that preliminary research indicates non-thermal plasma is safe for surrounding tissues, Sedghizadeh says he is optimistic about its future dental and medical uses.
“Plasma is the future,” Sedghizadeh states. “It’s been used before for other sterilization purposes but not for clinical medical applications, and we hope to be the first to apply it in a clinical setting.”
“We believe we’re the first team to apply plasma for biofilm disinfection in root canals,” Jiang adds.
Source:
University of Southern California
