Teeth whitening is probably the most common cosmetic question I get. Everyone wants whiter teeth, and the market is flooded with options. Strips, trays, LED kits, charcoal toothpaste, oil pulling, baking soda. It can be hard to know what is worth your money and what is just hype.
Let me give you a straightforward take on what works, what does not, and what to be careful with.
How tooth whitening actually works
The teeth you can see in your smile are made of two main layers. The outer layer is enamel, which is hard, slightly translucent, and somewhat porous. Underneath is dentin, which is yellower in color. The whiteness or yellowness of your teeth depends partly on the thickness of your enamel and partly on the color of the dentin underneath.
Stains accumulate over time on and within the enamel. Coffee, tea, red wine, tobacco, and certain foods all contribute. Some staining is on the surface and can be polished off. Some is absorbed deeper into the enamel and requires a chemical process to break it down.
Real whitening uses peroxide. Either hydrogen peroxide or carbamide peroxide, which converts to hydrogen peroxide once applied. The peroxide penetrates the enamel and breaks down the stain molecules. That is the mechanism. Anything that does not use peroxide is not actually whitening your teeth in any meaningful way.
What actually works
Professional in-office whitening. We apply a high-concentration peroxide gel to your teeth, usually in combination with a special light to accelerate the reaction. This is the fastest method, with results visible in a single one-hour appointment. It also costs the most.
Professional take-home trays. We make custom-fitted trays based on impressions of your teeth, then send you home with peroxide gel. You wear the trays for a set amount of time each day, usually 30 minutes to an hour, for one to two weeks. Custom trays produce significantly better results than generic strips because the gel stays in contact with the teeth and does not leak onto the gums.
Over-the-counter whitening strips. These do work, but the results are modest. The peroxide concentration in over-the-counter products is limited by regulation, which means slower and less dramatic results. If your teeth are mildly stained and you have a few weeks to commit to a daily routine, strips are a reasonable starting point. The main downside is that the strips do not fit your teeth precisely, so the results can be uneven, especially on slightly crooked teeth.
Whitening toothpastes. These contain mild abrasives and sometimes very low concentrations of peroxide. They can remove surface stains and prevent new ones from forming, but they will not actually change the underlying color of your teeth. Useful as a maintenance tool after professional whitening, not as a primary treatment.
What does not work
Charcoal toothpaste. The marketing is impressive but the science is not. Activated charcoal is abrasive and can scrub off some surface stains, but it does not penetrate the enamel and does not whiten the underlying tooth. Long-term use of charcoal toothpaste can actually damage enamel because of the abrasiveness, which over time can make teeth look more yellow as more dentin shows through.
Oil pulling. Swishing coconut oil or sesame oil in your mouth for 20 minutes a day has been promoted as a teeth whitener. There is no good evidence it whitens teeth. It is a waste of time.
Baking soda and lemon juice. The lemon juice is acidic enough to dissolve enamel. Do not put lemon juice on your teeth. The same applies to apple cider vinegar mixtures and other acidic home remedies.
Charcoal black peroxide gels from Amazon. Some of these contain unsafe concentrations of peroxide. Some contain other chemicals that should not be near your gums. If you want to try home whitening, stick with established brands or come see us.
What whitening does not fix
This is important.
Whitening works on natural tooth enamel. It does not change the color of crowns, veneers, bonding, or fillings. If you have restorations on your front teeth, your natural teeth will whiten but the restorations will not. The result can be a mismatched smile. We need to talk through your options before you start, because if you have visible restorations, you may need to have them replaced after whitening to match your new shade.
Whitening also does not work well on certain types of staining:
Tetracycline staining. Tetracycline antibiotics, when taken during tooth development in childhood, cause deep gray or brown banding inside the teeth. Whitening does not touch this. (For tetracycline staining and other deep intrinsic stains, porcelain veneers are usually the better path. See our post on porcelain veneers for more on that option.)
Trauma staining. A tooth that turned dark after an injury usually has internal damage that whitening cannot reach. Sometimes we can do internal bleaching, which is a different process. Sometimes a crown or veneer is the better solution.
Fluorosis. White or brown spots from too much fluoride during tooth development do not respond well to whitening. Cosmetic bonding or microabrasion are usually better options.
Side effects to know about
Tooth sensitivity is the most common side effect. The peroxide can irritate the nerves inside the teeth, causing temporary sensitivity to cold. This usually resolves within a few days of stopping treatment. Using a sensitivity toothpaste like Sensodyne for a couple of weeks before starting whitening helps.
Gum irritation can happen if the whitening gel touches the gums, especially with poorly fitting trays or strips. Custom-fitted trays minimize this.
Damage from over-whitening. Yes, this is a thing. Patients who whiten too aggressively or too frequently can damage the enamel and end up with teeth that are translucent at the edges, more sensitive long-term, and actually look worse. Whitening should not be a daily forever habit. It should be a course of treatment, then maintenance.
Where to start
Come in for a consultation and we will look at what is causing the discoloration, the type of staining you have, and what the best approach is. Sometimes the answer is professional whitening. Sometimes it is whitening followed by replacing an old restoration. Sometimes it is veneers. Sometimes it is just a thorough professional cleaning to remove surface stains, and you do not actually need whitening at all.
We will give you the honest take.
Call us at (509) 933-3300 to schedule a cosmetic consultation at our Ellensburg office.
Related reading: Why people in Kittitas County are fixing their smiles with veneers, How often should you actually get your teeth cleaned, A dentist who grew up here.