Science Foundation grant of more than $250,000 made University of Missouri-Columbia researchers Qingsong Yu and Hao Li two very happy engineers. Soon, perhaps, their good fortune will give us all a reason to smile.
Yu and Li are using the NSF funding to pioneer a dental technology that could take the anxiety out of trips to the dentist's chair. Their new "plasma brush" would replace the dental drill's noisy, sometimes painful spin -- a major cause of dental phobia -- with the silence and serenity of a low-temperature chemical reaction. It should also reduce an enormous waste that bites into nearly every dental practice, the tedious task of replacing failed fillings.
As the researchers envision it, the plasma brush will look much like its low-tech counterpart, the toothbrush, but with a slightly larger handle "hooked up to a few tucked-away gas tanks," Li says.
The new brush, Yu adds, will "save healthy tissue," which takes a beating from "mechanical drilling and acid etching in conventional preparation of cavities."
Clinical trials can't start soon enough for New York City-based cosmetic and reconstructive dentist Daniel Noor, whose Park Avenue practice already employs the latest in laser instrumentation.
"I am a firm believer in great technology," Noor says. "The plasma brush makes a lot of sense -- no shots, no drills, no pain, no fear. Though it's so unique most dentists have never heard of it, I would certainly use it after FDA approval."
Plasmas - electrically conductive gases packed with free-floating electrons - are the most abundant forms of matter in the universe. They swirl into clouds that condense into stars and power the fluorescent bulbs that flash across the Las Vegas night. Lightning, the Aurora Borealis and flat-panel television displays are some of the plasmas in our midst.
After working for years to develop a low-cost way to clean contaminated surfaces, Yu and Li -- both assistant professors of mechanical and aerospace engineering -- used argon gas to create a "plasma tip" shaped much like a tiny scrub brush.
Like the ethereal flame that dances at the tip of a welder's torch, their plasma brush operates at atmospheric pressure, a relatively new feature important for clinical applications.
"Non-thermal plasmas were formerly produced at reduced pressure using an expensive vacuum system that limited their biomedical applications," explains Yu. "Now, they can be operated in open air."
Plasma-treated tissues also remain free from thermal damage, Yu says. This is because their plasma brush is engineered to operate at a cool 42 degrees Celsius, about room temperature, making it an ideal disinfectant. There is no heat and no harmful chemicals.