Why do teeth get yellow? To figure out how to whiten our teeth, we have to know why they get yellow in the first place. There are several factors that play a part, including genetics, what kind of food and drink you consume, and how well you practice oral hygiene. A tooth is made up of 4 tissues-enamel, which is the strong white covering that protects the tooth, dentin, which supports the enamel and is a hard yellow material that carries nerves, pulp, which is at the center of the tooth and contains blood and lymph vessels, and cementum, which covers the root of the tooth.
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