A lot of people are worried about yellow teeth, so what is the cause of the teeth become yellow?
   First, the physiological changes tooth color
   People's teeth with age and long-term use, will gradually have mild color changes. Just like your skin, when you are young, white and smooth, when older gradually dull. These are inevitable. For such a color change do not care too much, if you are very concerned about the color of your teeth, you can use the method of whitening teeth to enhance the appearance, as well as skin beauty.
Ways to deal with: physiological changes in the teeth is difficult to avoid, you should develop a good habit of mouthwash after meals and brush teeth in morning as well as evening, which can help delay the process of yellowing teeth.
   Second, exogenous yellow teeth
   As the food pigment attached to the tooth surface, showing yellow or gray; smoking smoke, beverages, coffee, tea and other attached teeth will appear as yellow gray.
   ways to deal with: to develop a good habit of brushing teeth in the morning and evening, always keep the mouth clean and healthy, is an effective way to avoid exogenous yellow teeth.
   Third, endogenous yellow teeth
   Teeth are affected by some element, the pigment is not on the tooth surface and in the teeth tissue, there are two: dental fluorosis and tetracycline teeth.
   (1) dental fluorosis: This tooth is mainly before the age of seven, living in drinking water caused by high fluoride areas. Pigment in the tooth surface enamel, was yellowish brown patchy, severe tooth surface there are uneven defects, generally to the mandibular incisors for the obvious, thus seriously affect the appearance.
   (2) tetracycline teeth: these teeth are mainly related to the use of tetracyclines before age eight. Tetracycline molecules can be combined with calcium in the tooth tissue to form a very stable complex, deposited in the tooth tissue, make teeth colored, that full mouth teeth can be brown gray or brown yellow.
   The way to deal with: Due to endogenous causes of teeth yellowing, mostly whitening problem was intractable teeth, need to use scaling or some other professional tooth whitening method to relieve the symptoms of black and yellow teeth. However, the specific method of choice, need to be based on personal circumstances, consult a professional dentist and then choose.

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