Cavities are caused by plaque and bacteria in the mouth breaking down tooth enamel. Left untreated, cavities can grow deeper and cause pain. Symptoms include tooth sensitivity, pain when eating or drinking hot or cold foods, and visible holes in the teeth. Proper brushing and cleaning between teeth can prevent cavities by removing plaque and food debris before bacteria can produce acid that destroys enamel. Toothpaste ingredients like abrasives, detergents, and fluoride help clean teeth and remineralize enamel. Mouthwashes are used to fight bacteria and freshen breath. Pain relieving gels containing benzocaine or lidocaine can temporarily reduce tooth pain.