Black stains on teeth can be caused by using mouthwashes that contain the ingredient chlorohexedine or by taking iron supplements, explains 1-800-Dentist. Root canal sealers that contain silver or other dental restoration materials containing silver nitrates can also cause black tooth stains, notes Family Gentle Dental Care.
In addition to black staining, tooth stains can also be yellowish-brown, dark brown, white, green, orange or bluish-gray, notes 1-800-Dentist. Drinking large amounts of coffee, tea, soda or wine can result in stains that are yellowish-brown or dark brown. Both white and red wines can result in these types of stains. White stains indicate fluorosis, a condition that results from using too much fluoride. Unlike the brown stains that often result from drinking certain beverages, white fluorosis stains are a type of intrinsic stain, meaning they involve the inner layers of the affected teeth.
Green teeth stains are most often found on children's teeth, explains 1-800-Dentist. Exposure to certain chemicals, including copper, mercury and nickel, can cause this type of staining, as can fluorescent bacteria or fungi in the mouth. Orange stains are also most commonly found in children. They can result from either chromogenic bacteria or food buildup due to inadequate brushing and flossing habits. Lastly, the medication tetracycline is one cause of bluish-gray tooth stains.