Tooth Staining

Getting to the cause of tooth discoloration is the first step toward successful treatment

Dear Doctor,
My teeth seem to stain very easily. I have some new white fillings and I'm concerned that they will stain like the last ones did in my front teeth. How can I stop this?

Dear Ashley,
It's very important to first ascertain the cause of the staining in order to prevent it in the future. The topic of staining is quite complex, so here's a helpful guide.

There are basically two types of tooth staining or discoloration: extrinsic (external), which affects teeth from the outside; and intrinsic (internal), staining built into the structure of the tooth itself.

Extrinsic staining occurs because the microscopic pits, fissures and defects in the outer surface of tooth enamel are susceptible to the accumulation of stain-producing substances. These substances arise from a variety of sources: certain foods and beverages — particularly, red wine and tea with high tannin content, any form of tobacco, chromogenic (color or stain producing) oral bacteria, and topical medications. Any of these can be intensified by the accumulation of dental bacterial plaque, a result of inadequate oral hygiene.

Interestingly, many topical medications used for dental care have certain ingredients that can also cause staining. Mouthwashes containing chlorhexidine (0.12%), a prescription antibacterial mouthrinse, or those containing cetylpyridium chloride, can cause dental staining after long-term use, particularly on acrylic, composite resin and porcelain restorations. Stannous fluoride, a component of some toothpastes may also induce brown discoloration.

Once your dentist has identified the type and cause of staining, he or she can recommend an appropriate therapy.

Since saliva plays a major role in the physical removal of food debris from tooth surfaces, diminished salivary output may contribute to extrinsic discoloration. Diminished output that may lead to mouth dryness can arise from several causes such as salivary gland obstructions, chemotherapy, radiation treatments for cancer and multiple medications.

Intrinsic dental stains may arise from certain dental filling materials, next to adjacent tooth structure or the condition of the tooth itself. For example, if the tooth is largely replaced by filling material, or if it has had a root canal filling, it may have a different color than the adjacent teeth.

Getting to the Root Cause of Staining

The fact that you have had a previous problem can help your dentist determine what kind of stain you have and the underlying cause. Also, certain physical characteristics and observations can provide clues as to whether the stain is extrinsic or intrinsic:

• Extrinsic stain colors are commonly brown, black, or gray; however, they can also include green, orange, and yellow.
• Extrinsic staining may be removed by polishing, while intrinsic staining cannot.
• Teeth with intrinsic discoloration may be red or pink. Under ultraviolet light, teeth with tetracycline antibiotic staining (intrinsic) may fluoresce yellow.
• When a single tooth is discolored, an intrinsic stain is suspected and may demonstrate signs of pulpal (root canal) disease.

Treatment Options for Staining

Once your dentist has identified the type and cause of staining, he or she can recommend an appropriate therapy. Medical treatment may likewise be warranted, particularly if drugs are causing mouth dryness, which predisposes to staining.

Treatment options include:

• Diet and habit modification — develop a strategy for either modifying or eliminating habits — like tobacco use or the consumption of certain foods — that cause or contribute to staining.
• Effective twice daily oral hygiene — the use of an appropriate toothpaste helps to prevent extrinsic staining. Most toothpastes help with this because they contain an abrasive, a detergent, and an anti-tartar agent — and many now contain tooth-whitening agents.
• Professional tooth cleaning and polishing — Some extrinsic stains may be removed with ultrasonic cleaning, followed by polishing with an abrasive prophylactic paste or an air-jet technique with an abrasive powder. This “micro-abrasion” may occasionally be used with bleaching.
• Fillings and Restorations — teeth discolored by dental caries (decay) or dental materials require the removal of the decay or restorative materials, followed by proper restoration of the tooth. The junction between filling (restorative) materials replacing lost tooth structure and the adjacent healthy tooth is very important. Even with well-placed and properly handled materials, the junction is still subject to plaque accumulation and therefore staining.
• Bleaching (tooth whitening) — this technique is a safe and relatively easy way to brighten stained teeth, and is used to treat many types of tooth discoloration. Bleaching includes two general types of techniques: vital, which is performed on “vital” teeth, i.e. the nerves are living and the discoloration is usually extrinsic; and non-vital, typically used to treat discolored teeth associated with root canal treatment. While vital techniques can be performed in-office or at home, non-vital whitening is strictly performed as an in-office professional procedure.

Consult with your Dentist

As with any dental condition, it's important to discuss your concerns with your dentist. With your motivation and his or her expertise, you should arrive at a therapy that can reduce or eliminate your discoloration problem.