A new chemical could make human teeth 'cavity proof' - and do away with the need for visits to the dentists forever. The molecule has been called 'Keep 32' - after the 32 teeth in a human mouth. The chemical was designed by dentists in Chile, and wipes out all the bacteria that cause cavities in just 60 seconds in tests. The chemical could be added to any current dental care product, turning toothpaste, mouthwash and chewing gum into 'super cleansers' that could get rid of the underlying cause of tooth decay. The chemical targets 'streptococcus mutans', the bacteria that...