Tooth discoloration can occur as a result of surface stains, due to actual changes inside your tooth, or because of a combination of both factors. There are three main types of tooth discoloration:

  • Extrinsic: This occurs when the outer layer of the tooth (the enamel) is stained. Coffee, wine, cola or other drinks or foods can stain teeth. Smoking also causes extrinsic stains.
  • Intrinsic: This is when the inner structure of the tooth (the dentin) darkens or gets a yellow tint. You can get this type of discoloration if:

 

  • Your mother used tetracycline antibiotics during the second half of pregnancy. 
  • You used tetracycline antibiotics when you were 8 years old or younger.
  • You had trauma that affected a tooth when you were a young child. A fall, for example, may damage the developing permanent tooth.
  • You had trauma in a permanent tooth, and internal bleeding discolored the tooth.
  • You were born with a rare condition called dentinogenesis imperfecta. This causes gray, amber or purple discolorations.
  • Age-Related: This is a combination of extrinsic and intrinsic factors. Dentin naturally yellows over time. The enamel that covers the teeth gets thinner with age, which allows the dentin to show through. Foods and smoking also can stain teeth as people get older. Finally, chips or other injuries can discolor a tooth, especially when the pulp has been damaged.