Your teeth may become discolored for a variety of reasons. Dentists refer to discoloration on the surface of your teeth as extrinsic staining, whereas changes in color beneath the surface of your teeth are intrinsic staining. Extrinsic stains are often easier to bleach than intrinsic discolorations, explains Dr. Chris Sampair, of the University of Minnesota School of Dentistry. Whatever the cause of your tooth discoloration, however, consult your dentist prior to beginning any tooth whitening procedure.
Foods
Foods are a common culprit of extrinsic staining. Coffee, tea and red wine contain substances called tannins that may react with tooth enamel to deposit color on the surface of your teeth. Colored foods, such as blueberries and carrots, also contribute to surface discoloration, according to Everest College. Careful and consistent oral hygiene can help prevent the buildup of extrinsic stains on your teeth.
Tobacco
Use of tobacco products also causes extrinsic teeth discoloration. Tar compounds in tobacco, whether you smoke it or chew it, adhere to the surface of your teeth, causing stains. These dark brown or black stains commonly extend from mid-tooth to your gum line, states Dr. David Rolf, director of education at Dental1.org. While tobacco stains may be removed or lightened by bleaching, not using tobacco products prevents these stains from forming in the first place.
Age
Due to years of chewing, exposure to acidic foods and a buildup of abrasions, the process of aging contributes to extrinsic teeth discoloration. These factors help wear away your tooth enamel, leaving your teeth less protection against staining from external sources. Also, tiny cracks that develop in your tooth surface as you age allow small particles of food to cling to your teeth, causing discoloration if they are not thoroughly and regularly cleaned.
Fluoride
Fluoride is a primary cause of intrinsic teeth discoloration. Known as dental fluorosis, this staining occurs when your teeth are exposed to high levels of fluoride, either in community drinking water or through ingestion of fluoride-containing dental products. This staining may show up as spotting or pitting on the enamel of your teeth. While fluoride in drinking water helps prevent tooth decay in children, avoid excessive fluoride exposure as an adult to minimize your risk of dental fluorosis, which leaves teeth discolored.
Tetracycline
The antibiotic tetracycline may cause intrinsic staining when developing teeth are exposed to it. This exposure may occur during pregnancy or during a child's early years, resulting in gray- or brown-stained teeth when the child reaches adulthood. Sampair says that tetracycline stains dentin, which is the tooth tissue located beneath the surface of the enamel, making it difficult, although not impossible, to bleach.
Trauma
Trauma to your mouth may cause gray or brown staining beneath the enamel surface of your teeth. If the trauma is severe enough, the pulp tissue deep within your teeth may die, and the release of iron from the dead tissue causes teeth discoloration. If the dead pulp is not removed through an endodontic procedure, the staining of your teeth may be permanent.
