If the symptoms of bleeding teeth only appear, it is usually not a precursor of AIDS, it may be related to physiological factors such as brushing teeth with greater strength, or it may be caused by gingivitis, periodontitis and other diseases. 1. Physiological factors: If you brush your teeth with too much force, the periodontal skin may be damaged, and bleeding may occur. 2. Gingivitis: the cause of its formation may be related to the plaque that accumulates in the dental area, smoking and other factors, the clinical manifestation is bleeding when brushing or biting hard objects. 3. Periodontitis: the main symptoms are red and swollen gums, bleeding on probing, loose teeth, bleeding on brushing, etc. The causes are mostly related to plaque, tartar and traumatic biting. If only bleeding teeth, generally does not mean that it is a precursor to AIDS, leading to more causes of bleeding teeth, after excluding physiological factors, it is recommended to go to a regular hospital to find out the cause.