Many types of food and drinks can stain children's teeth. Next to poor dental hygiene, one of the most common reasons for black teeth is bottle rot, also called caries or nursing bottle syndrome. Decay from the sugar in juice or milk when a baby falls asleep with a bottle can turn baby teeth black. Older children can develop discolouration in their teeth from foods and drinks such as berries, cherries, potatoes, soy sauce, tea, coffee, and soft drinks such as cola in addition to food or vitamins containing a lot of iron. Food containing high fructose corn syrup used for any length of time can discolour and decay teeth. Young children with bottle rot should see a dentist right away.
Diseases and Medication
Some diseases affect the hard surface covering the teeth, which is called the enamel. Others affect the dentine, which is the material under the enamel. Salivary dysfunction that disrupts the part that saliva plays in removing food and other materials from teeth can cause dark spots on teeth. Sickle cell anaemia, leukaemia, cancer, diabetes, measles, chickenpox, strep infections and scarlet fever can cause discolouration of tooth enamel. Pregnant mothers with infections can affect the development of babies' tooth enamel, causing children's teeth to turn black when they come in. There are several hereditary diseases that can cause black teeth in children. Medications can also cause children's teeth to darken. Antibiotics such as tetracycline and antihistamines such as Benadryl can stain and darken a child's developing teeth. Pregnant mothers taking tetracycline can cause their children's teeth to blacken in the future.
Fluoride and Minerals
Fluoride protects teeth, but too much fluoride in the water or in toothpaste can darken children's teeth. Many children swallow toothpaste, and that can cause their teeth to turn black. Children under 3 should use toothpaste with no fluoride to avoid black teeth. Minerals from well water can also darken developing teeth, especially when the children have a disease that prevents protective tooth enamel from forming. Buying nursery water and using it for baby bottles, food preparation, drinking and teeth brushing can prevent black teeth caused by well water. Proper dental hygiene should be used as soon as a child gets a tooth. Teeth should be brushed on every surface using a circular motion for 2 to 4 minutes, and flossing between teeth is important.