Most people have teeth with a hint of yellow, brown or gray coloring.
Discoloration of teeth can be caused by various factors. As people age, their teeth tend to darken usually due to stains picked up from drinking tea and coffee or smoking and from a change in the tooth structure which makes it less transparent. Fillings, crowns and other restoration in the mouth also can stain teeth. Teeth cleaning should be done every six months to one year, with the frequency depending in part on the amount of coffee and tea you drink. Brushing regularly is also necessary to control teeth staining.