What causes teeth stains?
First and foremost, there are two types of stains: exterior and interior. As the name implies, exterior stains are found outside the tooth particularly on the enamel. Interior stains are found inside the tooth.
Teeth differ from one person to another. Some people have defects on the outer covering of the tooth enamel: microscopic cracks and holes that can make colored substances stick more to the enamel’s surface.
Also, a genetic condition where a person has less saliva than what is normal is predisposed to staining. Saliva washes away debris from food and drinks. If the person produces less saliva, then the mouth is washed infrequently.
Teeth gradually stain yellow with aging, but poor dental habits are more responsible for this.
The following are sources of exterior stains of the teeth:
All food can deposit leftover materials and pigments on the teeth causing gradual yellowing of the teeth through time. Some food may also cause immediate staining due to natural pigments colored substances (e.g. berries) or due to food coloring (e.g. candies)
Beverages that contain tannic acid (e.g. coffee and tea) or other acids such as phosphoric (e.g. cola drinks) can cause brownish stains on the teeth. The acid reacts with the enamel and stains the teeth yellow. Red wine is not highly acidic being an alcohol, but bacteria living in the mouth can react with it changing it to an acid.
3. Exposure to metallic salts
People who work in chemical factories may inhale fumes of metallic salts such as copper, nickel, potassium, calcium, sodium, silicon, magnesium, and phosphorus causing green stains on the teeth.
4. Tobacco Use
Smoking or chewing tobacco can leave brown to black stains on the middle surface of the tooth down to the gums. These stains are hard to remove and gets worst with prolonged smoking.
Color-producing bacteria (chromogenic) cause orange to red stains. Black stain, the most common stain caused by bacteria is caused by Actinomyces sp. Fluorescent bacteria produce green stains on the teeth. Bacteria react on the food we eat and excess acids can react with the enamel of the tooth and cause plaque and eventually tooth decay.
6. Medicated mouthwash
Some medications delivered as mouthwash can gradually stain the teeth as well. These include Iodine-containing, Chlorhexidine, Iron-containing (black), Potassium Permanganate (violet-black), Silver Nitrate (black), and Stannous Flouride (brown) mouthwashes.
Antibiotics such as Tetracycline and Minocycline stain the teeth by interfering with the developing teeth. For this reason, Tetracycline is not given to children.
2. Exposure to excess amounts of Flouride
Excessive exposure to fluoride due to treated water from public facilities, and fluoride-containing toothpastes, as well as fluoride supplements can cause staining by interfering with developing teeth. The teeth takes on an uneven whiteness.
Some people have hereditary dentin conditions that make them prone to intrinsic staining of the teeth. The dentin is responsible for reflecting light that accounts for the color of the teeth that we actually see.
Hereditary blood conditions (e.g. erythropoietic prophyria) that make the pigment porphyrin, (in the blood) more attracted to calcium may cause interior staining as calcium deposits inside the tooth.
When a person suffers a heavy blow on the mouth, some of the tissue and blood vessels may decay and cause staining and discoloration of the teeth. This is because the dead cells and blood are deposited into the teeth.