There are many different factors that can cause tooth discoloration. An abnormally colored tooth is anything other than the yellowish-white to the white color of normal teeth. The factors that contribute to tooth color include congenital conditions, genetics, infections, and environmental factors. Abnormal color and shape may be caused by a malfunction in body processes. Some of these factors can influence the way your child’s enamel is formed, while others simply stain the enamel. Teeth may be uniformly discolored or it may appear as spots or lines in enamel. In addition, discolored areas may have a different density and porosity than normal enamel. The color and hardness of enamel can also be affected by drugs or medications taken by either the child during the time of tooth development or by the mother while pregnant.