There are four types of teeth - incisors, canines, premolars, and molars - each with a different function like cutting, tearing, and chewing. Teeth are made of enamel, a hard substance. Bacteria in plaque produces acid that attacks teeth and causes cavities over time if plaque is not removed regularly through brushing at least twice daily, flossing, and visiting the dentist twice per year. Eating a balanced diet with foods that do not cause decay and taking care of gums also contributes to strong, healthy teeth.