Dental caries afflict at least 90% of the world’s population at some time in their lives. Detecting the first signs of this disease, which can be lethal in extreme cases, just got easier thanks to work by researchers in India discussed in the latest issue of the International Journal of Biomedical Engineering and Technology. R. Siva Kumar of the Department of Electronics and Communication Engineering, at RMK Engineering College, in Tamil Nadu, explains that dental caries, known colloquially as tooth decay or dental cavities, is an infectious disease which damages the structures of teeth. The disease causes toothache, tooth loss, infection of the jawbone and beyond, and in severe cases, death. Caries are caused by acid-producing bacteria that feed on fermentable carbohydrates including sucrose, fruit sugars, and glucose. The higher level of acidity in the mouth due to this bacterial activity effectively dissolves the mineral content of the tooth. In the USA, dental caries is the most common chronic childhood disease, being at least five times more common than asthma. It is the primary cause of tooth loss in children, while between a third and two thirds of people over 50 years experience caries too.