Why do some people have bright white teeth, while others are really yellow and black? What are the causes of tooth discoloration? According to Astor experts, the main causes of tooth discoloration are: 1, dead pulp teeth (trauma, dental caries → pulp necrosis), smoking, drinking tea and coffee, etc. 3. Iatrogenic tooth discoloration: such as tooth discoloration after plasticizing treatment, filling and desensitization treatment. 4. Tetracycline teeth (permanent teeth): caused by taking tetracycline drugs before the age of 7. Tetracycline can be deposited in the hard tissue of developing teeth, mainly in dentin, making all teeth brown or brownish yellow or grayish brown. 5. Dental fluorosis or mottled enamel: It is caused by living in areas with high fluorine content in drinking water before the age of 7. Pigment is yellow-brown plaque in enamel on the tooth surface, and in severe cases, there are pits on the tooth surface. Generally, the front teeth are the most obvious. 6. Enamel hypoplasia and calcification: During the tooth development, due to systemic diseases, such as fever, viral infection and systemic infection, the metabolism and nutrient absorption of the body are affected, which leads to the staged development of the teeth, resulting in partial defect or calcification of the crown, which is easy to collapse and destroy the tooth shape. How to solve tooth discoloration? The best solution is cold light whitening teeth. Finally, Astor experts remind you that you must choose a regular plastic surgery hospital for tooth whitening. [Editor: Rowling]