Featured Research

from universities, journals, and other organizations

Wiping Out Tooth Infections: Cool Plasma Packs Heat Against Biofilms

Date:
June 15, 2009
Source:
University of Southern California
Summary:
Miniature plasma -- silent and cool to the touch -- wipes out tenacious infections quickly and easily in teeth. The technology could eventually replace some antibiotic treatments for battling local infections.

The plasma probe is applied to an extracted tooth.
Credit: Image courtesy of University of Southern California

Though it looks like a tiny purple blowtorch, a pencil-sized plume of plasma on the tip of a small probe remains at room temperature as it swiftly dismantles tough bacterial colonies deep inside a human tooth. But it's not another futuristic product of George Lucas' imagination. It's the exciting work of USC School of Dentistry and Viterbi School of Engineering researchers looking for new ways to safely fight tenacious biofilm infections in patients – and it could revolutionize many facets of medicine.

Two of the study's authors are 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.

Sedghizadeh explained that biofilms are complex colonies of bacteria suspended in a slimy matrix that grants them added protection from conventional antibiotics. Biofilms are responsible for many hard-to-fight infections in the mouth and elsewhere. But in the study, biofilms cultivated in the root canal of extracted human teeth were easily destroyed with the plasma dental probe, as evidenced by scanning electron microscope images of near-pristine tooth surfaces after plasma treatment.

Plasma, the fourth state of matter, consists of electrons, ions, and neutral species and is the most common form found in space, stars, and lightning, Jiang said. But while many natural plasmas are hot, or thermal, the probe developed for the study is a non-thermal, room temperature plasma that's safe to touch. The researchers placed temperature sensors on the extracted teeth before treatment and found that the temperature of the tooth increased for just five degrees after 10 minutes of exposure to the plasma, Jiang said.

The cooler nature of the experimental plasma comes 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 said.

"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, she said.

Sedghizadeh said the oxygen free radicals might be disrupting the cellular membranes of the biofilms in order to cause their demise and that the plasma plume's adjustable, fluid reach allowed the disinfection to occur even in the hardest-to-reach areas of the root canal.

Given that preliminary research indicates that non-thermal plasma is safe for surrounding tissues, Sedghizadeh said he was optimistic about its future dental and medical uses. Much like the spread of laser technology from research and surgical applications to routine clinical and consumer uses, plasma could change everything; especially since nonthermal plasmas don't harbor the risks of tissue burns and eye damage that lasers do, he said.

"Plasma is the future," Sedghizadeh said. "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 added. "This collaboration is very unique. We're attacking frontier problems, and we're happy to be broadening our fields."


Story Source:

The above story is based on materials provided by University of Southern California. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jiang et al. Nanosecond Pulsed Plasma Dental Probe. Plasma Processes and Polymers, June 2009; DOI: 10.1002/ppap.200800133

Cite This Page:

University of Southern California. "Wiping Out Tooth Infections: Cool Plasma Packs Heat Against Biofilms." ScienceDaily. ScienceDaily, 15 June 2009. <www.sciencedaily.com/releases/2009/06/090610154503.htm>.
University of Southern California. (2009, June 15). Wiping Out Tooth Infections: Cool Plasma Packs Heat Against Biofilms. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2009/06/090610154503.htm
University of Southern California. "Wiping Out Tooth Infections: Cool Plasma Packs Heat Against Biofilms." ScienceDaily. www.sciencedaily.com/releases/2009/06/090610154503.htm (accessed April 18, 2014).

Share This



More Health & Medicine News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) Video provided by AP
Powered by NewsLook.com
Is Apathy A Sign Of A Shrinking Brain?

Is Apathy A Sign Of A Shrinking Brain?

Newsy (Apr. 17, 2014) A recent study links apathetic feelings to a smaller brain. Researchers say the results indicate a need for apathy screening for at-risk seniors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins