Cavities and tooth decay are among the world’s most common health problems. Cavities are permanently damaged areas in the hard surface of your teeth that develop into tiny openings or holes. They can occur on any surface of a tooth, including the enamel, root surfaces and gums. Tooth decay is caused by dental plaque – a sticky film of bacteria that constantly forms on your teeth. The bacteria in plaque convert the sugar in your food into acids when they’re not cleaned regularly. These acids attack the tooth enamel, causing cavities to form. If cavities aren’t treated, they get larger and affect deeper layers of your teeth. They can lead to a severe toothache, infection and tooth loss. Plaque that stays on your teeth can harden under or above your gum line into tartar, making plaque more difficult to remove and creating a shield for bacteria.