Clarkson professor perfects polishing of teeth

POTSDAM — Perfectly polished teeth — down to the nanometer — could be the answer to preventing cavities, according to a study by a Clarkson University professor.

Igor Sokolov, a professor in the Center for Advanced Materials Processing and director of the university's Nanoengineering and Biotechnology Laboratories, used silica nanoparticles to finely polish teeth.

Along with graduate student Ravi M. Gaikwad, he found that teeth polished in that way were so smooth that it was difficult for bacteria to build up and cause cavities. The findings were published in the October issue of the Journal of Dental Research.

"These bacteria are our own bacteria. They're not that bad, but what they do in the presence of glucose or simple sugar is to create acid, which simply erodes tooth enamel. That's how cavities are created," Mr. Sokolov said.

The researchers used polishing technology originally developed for the semiconductor industry to polish a tooth to the nanoscale level — or thousands of times smaller than a grain of sand.

Mr. Sokolov said that he and Mr. Gaikwad found that teeth polished using their formula became too "slippery" for bacteria responsible for damage to enamel to build up.

"We had silica particles left over from previous projects, and I had the middle tooth of my daughter," Mr. Sokolov said. "So it was a natural combination."

The researchers compared their formula with professional toothpastes and polishes used by dentists, and found a tenfold improvement in the smoothness of teeth using the nanoparticles.

Using microscopy, Mr. Sokolov and Mr. Gaikwad were able to see what happened when they simulated brushing and rinsing action on the newly smoothed tooth. Bacteria were whisked away easily on the ultra-slick surface.

"We started to ask if bacteria could really see the difference," Mr. Sokolov said. "So we used microscopy not only to look at the tooth surface, but to mimic one whisker of a toothbrush, which we moved very fast over the surface of the tooth to mimic a toothbrush on a micron level, and see how the bacteria were removed first from the highly polished areas."

It would take a considerable amount of brushing to get that kind of result with a regular toothbrush and toothpaste, Mr. Sokolov said, adding that it's also next to impossible to clean every crevice of every tooth using those implements.

Several private companies are in contact with Mr. Sokolov to discuss bringing the dental technology to the market.