Teeth can become discolored by stains on the outer surfaces or by changes from inside. Therefore, teeth discoloration can be classified as extrinsic or extrinsic.
Extrinsic discoloration occurs mainly due to our food. Coffee, wine, and smoking are the main ones.
Intrinsic discoloration occurs when the inner structure of the tooth darkens or gets a yellow tint. This might happen for various reasons including:
Trauma on a tooth leading to internal bleeding
Trauma on a baby tooth may also damage the developing permanent tooth underneath.
Use of tetracycline either by your mother during her pregnancy of you, or during your childhood. Tetracycline can change the color of the developing teeth before they erupt in the mouth.
Exposure to high fluoride also may leave the teeth with white spots.