Scientists in Japan have created a microscopically thin film that can coat individual teeth to prevent decay or to make them appear whiter.

(Don’t get too excited though.  It will take 5 years or more before the film could be used in practical dental treatment such as covering exposed dentin, but it could be used cosmetically within three years.  If it means I don’t need to have my teeth sand-blasted every year, I’m all for it.)