Types of Tooth Discoloration
Your teeth can become discolored by stains on the surface or by changes inside the tooth. 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:
- You had too much exposure to fluoride during early childhood.
- 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.
Some tooth discoloration can be removed with professional cleaning. An example would be the stains caused by coffee. Many stains are permanent, however. Teeth sometimes can be whitened with a bleaching gel. In some cases, if the discoloration is severe, a crown or veneer may be required to cover it.
Brushing your teeth after every meal will help to prevent extrinsic stains. Dentists recommend that you rinse your mouth with water after having wine, coffee or other drinks or foods that can stain your teeth. Regular professional teeth cleaning will also help to remove surface stains.
Intrinsic stains that are caused by damage to a nerve or blood vessel in a tooth sometimes can be prevented. You may need to have root canal treatment to remove the inner part of the tooth (the pulp) before it has a chance to decay and darken. However, teeth that have root canal treatment may darken anyway.
To prevent intrinsic stains in children, avoid exposure to fluoride before the age of 4. Once the enamel is formed, fluoride will not discolor teeth.
Many extrinsic stains caused by food and drink can be removed by regular professional cleanings and home care. Good home care includes brushing, flossing and rinsing after meals.
Discoloration often can be removed professional in-office whitening procedure, which causes the teeth to get significantly whiter in about an hour. Several follow-up treatments may be needed, or take-home bleaching trays may be provided.
Professional teeth whitening take-home kits are also available, where your dentist will provide you bleaching gel and a customised mouth tray. The bleaching gels designed for use at home aren’t as strong as those applied by your dentist. This means that the process takes longer — usually two to four weeks.
You also can buy whitening products over the counter. They contain weaker bleach than the products you can get from your dentist. The whitening agent is applied as a gel placed in a mouthpiece or as a strip that sticks to your teeth. Over-the-counter mouthpieces fit less securely than the kind you get from your dentist, but they will lighten your teeth over time.
Whitening toothpastes may remove minor stains. They do not actually change the overall color of your teeth.
If your tooth has darkened after a root canal, bleaching the enamel will not help. Your dentist can apply a bleaching material to the inside of the tooth, or you may consider a crown or veneer.
When To Call a Professional
Tooth discoloration is mainly a cosmetic problem. Visit a dentist if you are unhappy with how your teeth look. Any change in a child’s normal tooth color should be evaluated by a dentist.