If tasting something hot or cold is painful on your teeth, you may suffer from sensitive teeth. It is a common problem that may be caused by worn tooth enamel or an exposed tooth root. Tooth enamel protects the crowns of healthy teeth and cementum protects the tooth root under the gum line. When the dentin that is underneath the enamel and cementum loses its protective covering, hot, cold, acidic or sticky foods reach the nerves and cells inside the tooth causing hypersensitivity. Following proper oral hygiene helps prevent the gums from receding and causing the pain of sensitive teeth.