In personal and social communications, a pretty smile plays an important role in people’s success. Healthy and white teeth have a great effect on people’s smiles. On the other side, discolored and irregular teeth, create an undesirable image in the audience’s mind, unconsciously and indirectly affects success negatively. A cosmetic process called tooth whitening or bleaching aims to whiten the color of the tooth. Although it does not completely convert dental color to white, it lightens the teeth color to a high degree without damaging its surface. The result of bleaching is not permanent, but it can last between several months to three years, and the duration varies between one patient and another. It lasts for a longer period if the person does not take materials that stain the tooth. The most common factors that cause tooth discoloration are tobacco and beverages like tea, coffee, and red wine. Also, aging along with thinning the enamel and not paying attention to teeth cleanings make teeth darker.