Solar: alternative energy, alternative toothbrush

University of Saskatchewan dentistry professor emeritus Dr. Kunio Komiyama and his colleague Dr. Gerry Uswak are recruiting 120 teens willing to brush with a prototype light-powered toothbrush and sit in a dentist's chair for a few extra inspections.

The manufacturer, the Shiken company of Japan, is paying the researchers to investigate whether the brush, which causes a chemical reaction in the mouth, does a better job of eliminating plaque and bacteria than a conventional toothbrush.

Komiyama's first model, which was described 15 years ago in the Journal of Clinical Periodontology, contained a titanium dioxide rod in the neck of the brush, just below the nylon bristles.

It works when light shines on the wet rod, releasing electrons. Those electrons react with acid in the mouth, which helps break down plaque. No toothpaste is required.

Now Komiyama's back with a newer model, the Soladey-J3X, which he says packs twice the chemical punch compared to the original. Protruding from the base of the brush is a solar panel, which transmits electrons to the top of the toothbrush through a lead wire.

It won't work in the dark, though - the brush needs about as much light as a solar-powered calculator would to operate.

In the lab, Komiyama tested the newer brush on cultures of two types of bacteria which are major culprits in periodontal disease.

"You see complete destruction of bacterial cells," he said.

At the FDI Annual World Dental Conference in Dubai last month, the team's poster describing the lab research won first prize out of 170 entries, which gives Komiyama confidence there is scientific merit to the brush.

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