Our teeth tend to be whiter during childhood. This is due to the fact that the enamel coating of deciduous/milk teeth is not as transparent as permanent teeth. Dentin, which is the layer underlying the enamel, is yellow in color. As we age, the yellow-colored dentin layer continues to develop and thicken. Also, the enamel coating can also get eroded due to poor oral hygiene and consumption of food items that are rich in sugars. While the presence of white, yellow, tan, brown, or black stains on the teeth might sometimes be only a cause for cosmetic concern, it's advisable to consult a dentist to identify the underlying cause and treat it at the earliest. More often than not, following a proper oral hygiene regimen can prevent the condition from worsening. However, treatment might be required when the discoloration is accompanied by other dental problems. Poor Oral Hygiene In majority of cases, discoloration of the teeth can be attributed to poor oral hygiene. Unfortunately, maintaining dental health and hygiene has taken a backseat. Problems arise in case of individuals who don't floss and brush their teeth regularly. Also, most individuals avoid going to the dentist until the pain becomes unbearable. Along with the lack of oral hygiene, dietary habits also play a role in the development of stains on the teeth. Diet Excessive consumption of coffee, tea, wine, colas, etc., can also be a reason behind the development of stains on one's teeth. These foods and beverages contain chromogens and/or tannins, which are responsible for damaging the enamel coating and promoting the development of stains. Also, acidic foods and beverages can erode the enamel and make it easier for the chromogens to bind to the enamel. Following a diet that is rich in sugar is another contributing factor. Plaque refers to a film of sticky bacteria and mucus that covers the surface of the teeth. It forms when bacteria come in contact with food and saliva. When one consumes sugar-rich food items, and the sugar comes in contact with plaque, it results in the formation of acid. This acid damages the enamel, thereby making one susceptible to a host of dental problems. If plaque is not removed, it hardens to form tartar. Dental Caries Dental caries, which is commonly referred to as tooth decay or cavity, is most likely to occur when a person does not brush his teeth regularly. As a result, the bacteria start acting on food debris that gets lodged between the teeth. This can lead to slight discoloration of the teeth. Over time, the structure of tooth gets demineralized. If it is left untreated, it may progress to the dentin and pulp, thereby giving rise to pain. If the caries has not reached the pulp, tooth decay can be treated by a simple cavity filling procedure. However, if the caries has reached the pulp, root canal treatment or tooth extraction might be recommended. Smoking and Chewing Tobacco Black spots on teeth are often observed in individuals who smoke. Smoking is one of the common causes for discoloration of the front teeth. Also, chewing tobacco leads to brown or black teeth. In the long run, smoking and chewing tobacco not only have a long-lasting effect on the dental health, but also make one susceptible to cancer. Hence, it is best to quit such harmful habits at the earliest, and visit the dentist to get the teeth cleaned and treated. On a concluding note, black stains on teeth should not just be seen as a cosmetic problem, but also as an indicator of poor oral hygiene. Thus, it is advisable to consult a dentist not only for the removal of stains, but for keeping your teeth healthy. Do follow a proper oral hygiene regimen, and visit the dentist every six months. Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a dentist.