The tooth is black and painful may be caries, but also may be pulpitis and periapical inflammation. 1. Dental caries: black teeth are mostly pigmentation of carious cavities. The affected teeth will appear sensitive to hot and cold stimuli, eating and drinking food blockage or hot and cold stimuli into the cavity, there will be pain and other symptoms, but the stimulus disappears, the symptoms disappear. 2. Pulpitis and periapical inflammation: The gradual development of caries will cause pulpitis and periapical inflammation. Pulpitis will cause spontaneous pain, radiating pain, etc. Apical periodontitis is mainly occlusal pain. There may be other reasons for the tooth to be black and painful, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.