Why do my two front teeth have black dirt when I don't smoke or drink tea?

-_-|| Your oral care is not good enough at ordinary times. First, if you don't drink water after eating, food residue will stay on your teeth. Second, brushing your teeth in the morning is not serious. Other teeth are easier to clean, because saliva and tongue are moving when talking, which plays a certain role in cleaning up the residue. Front teeth are more difficult to clean. I suggest you buy whitening toothpaste and a toothbrush with little damage to gums, and focus on cleaning front teeth, brushing off black dirt and brushing off dirt on yellow teeth. You can also go to the dentist to have your teeth cleaned regularly.