There four major tissues which compose the tooth: enamel, dentin, cementum and pulp. Dental enamel is the hardest tissue not only in the tooth but also in the whole human body. Like any part of organism tooth enamel contains water and organic component but only 4% in total and other 96% go to the mineral compounds. The natural color of tooth enamel can be different: from light yellow to grayish white. But a teeth color in general depends not only on enamel color because the enamel is semitransparent. That is why underlying dentin has a great influence on the appearance of a tooth. Also certain elements of everyday life like coffee, tea, tobacco as well as bacteria stains are able to provoke a discoloration of tooth enamel. The main mineral of enamel is a calcium phosphate.
