Extrinsic discoloration chewer in Burma Extrinsic discolorations are common and have many different causes. •
Dental plaque: Although usually virtually invisible on the tooth surface, plaque may become stained by chromogenic bacteria such as
Actinomyces species. •
Tobacco:
Tar in smoke from tobacco products (and also
smokeless tobacco products) tends to form a yellow-brown-black stain around the necks of the teeth above the gumline. • Pigments in food and drink may cause staining if frequently consumed. Foods, such as vegetables, that are rich with
carotenoids or
xanthonoids can stain teeth. Ingesting certain drinks, such as
tea,
coffee,
red wine and
cola, may cause staining. Frequent consumption of
black tea can cause tooth discoloration due to high levels of
theaflavin and
tannins. • Certain topical medications. •
Chlorhexidine (
antiseptic mouthwash) binds to
tannins, meaning that prolonged use in persons who consume coffee, tea or red wine is associated with extrinsic staining (i.e., removable staining) of teeth. •
Cetylpyridinium chloride, which is found in many
antimicrobial mouthwashes, can result in staining due to dead bacterial residue. • Metallic compounds. Exposure to such metallic compounds may be in the form of medication or other environmental exposure. Examples include iron (black stain), iodine (black), copper (green), nickel (green) and cadmium (yellow-brown). • Antibiotics. Tetracycline and its derivatives are capable of intrinsic discoloration (discussed below). However other antibiotics may form insoluble complexes with calcium, iron and other elements that cause extrinsic staining.
Dental caries Dental caries (tooth decay) begins as an opaque white spot on the surface of the enamel. As demineralization progresses, the various lesion eventually cavitates and the underlying brown color becomes visible.
Trauma Dental trauma may result in discolorations.
Root canal treatment Internal staining is common following
root canal treatment; however, the exact causes for this are not completely understood.
Amalgam fillings Amalgam fillings often stain the tooth they are placed in. The drug is able to
chelate calcium ions and is incorporated into teeth, cartilage and bone. Ingestion during the years of tooth development causes a yellow-green discoloration of dentin, which is visible through the enamel and fluorescent under ultraviolet light. Later, the tetracycline oxidizes and the staining becomes more brown and no longer fluoresces under UV light. Other drugs derived from tetracycline such as
glycylcycline share this side effect. Because tetracyclines cross the placenta, a child may have tooth staining if the drugs are administered during the mother's pregnancy. This is possibly the result of exposure to tetracycline during odontogenesis, however
cystic fibrosis transmembrane regulator has also been demonstrated to be involved in enamel formation, suggesting that the disease has some influence on tooth discoloration regardless of exposure to tetracyclines.
Aging Intrinsic discoloration tends to accompany aging. Throughout life deposition of secondary dentin occurs along the internal walls of the pulp chamber. Secondary dentin is darker and more opaque than primary dentin. This gives the dentin an overall darker appearance. At the same time, the enamel layer is gradually thinned by tooth wear processes such as attrition and acid erosion, a degree of which is considered normal. Enamel also becomes less porous and phosphate-deficient. ==Management==