Teeth Whitening: Dentist vs At-Home Options, and Why Teeth Get Sensitive

Is whitening better at the dentist or at home?

Neither route is better for everyone. The ADA lists three ways to whiten: in-office bleaching, dentist-supplied products you use at home, and over-the-counter products. They use the same kind of bleach at different strengths and with different amounts of supervision.

Dentist care starts with an exam. The ADA says a clinical exam before bleaching, with X-rays and other tests as needed, can help find what is behind your tooth color. That matters because not every stain responds to bleach.

The table compares the routes.

The ADA says over-the-counter products tend to cost less but may take significantly longer to reach similar results. One study the ADA cites found a store bleaching method took 16 days to reach the level of a seven-day tray system and a one-day in-office procedure.

Your dentist can tell you which route fits your teeth and your schedule.

Why do teeth change color?

Teeth change color for many reasons, and the cause affects what whitening can do. The ADA lists these causes:

• Food and drink. Coffee, tea, and red wine are major staining culprits.
• Tobacco. Tar and nicotine create stubborn stains.
• Age. The outer enamel layer thins, and the yellower layer underneath shows through.
• Trauma. A tooth that is hit may darken as it lays down more dentin.
• Medications. Some antihistamines, antipsychotics, and blood pressure medicines can darken teeth. Certain antibiotics taken during tooth formation can cause discoloration. Chemotherapy and head and neck radiation can also darken teeth.

Dentists divide stains into two groups. Surface stains sit on the enamel. Deeper stains sit inside the tooth. The ADA says whitening can work on both kinds, though the type of stain can change how many treatments you need. Our glossary entry on tooth discoloration explains the types, and the entry on dentin shows why aging teeth look yellower.

Will whitening work on all of my teeth?

No. The ADA says yellow teeth will probably bleach well, brown teeth may not respond as well, and teeth with gray tones may not bleach at all. It also says whitening may not help if the discoloration comes from medications or a tooth injury.

Whitening also does not change restorations. The ADA says it will not work on caps, veneers, crowns, or fillings. Only natural tooth color changes. If a front tooth has a crown or a filling, the restoration stays the same shade when the rest of your teeth lighten.

This affects planning. Many people whiten first, then match new work to the lighter shade. Ask your dentist about the order if you also need fillings or crowns.

What does a whitening visit involve?

In-office bleaching usually takes one visit, according to the ADA. The dentist applies either a protective gel to your gums or a rubber shield. Then the bleach goes on your teeth. Some systems use a light to speed the process. The ADA notes that some systems may be used with or without light.

Take-home whitening works differently. Your dentist makes a custom tray, shows you how to load the bleach, and tells you how long to wear it. The ADA says this may suit you if you want to whiten at your own pace with a dentist’s guidance. It can take from a few days to a few weeks.

Either way, the steps look like this:

1. A dentist checks your teeth and gums and talks about your goals.
2. The dentist explains which stains are likely to respond.
3. The dentist protects your gums and applies bleach, or makes trays.
4. You follow the timing exactly.
5. You return for a check if your dentist asks.

How does whitening work?

Whitening products use hydrogen peroxide or carbamide peroxide, a form of teeth whitening bleach. The ADA says these bleaches break stains into smaller pieces, which makes the color less concentrated and your teeth brighter. Because peroxide must reach the stain to work, it passes through the enamel.

Whitening toothpastes work differently. All toothpastes remove surface stain through mild abrasives. Whitening toothpastes with the ADA Seal for stain removal add polishing agents. The ADA says these do not change the color of teeth like a bleach does, because they only remove surface stains.

Why do teeth get sensitive after whitening?

Sensitivity happens because the peroxide reaches the softer layer under the enamel and irritates the nerve, which is a form of tooth sensitivity. The ADA says that in most cases the sensitivity is temporary. The ADA’s longer review says temporary tooth sensitivity and gum irritation are the most common side effects of whitening.

It is also common. An ADA review says mild to moderate sensitivity can occur in up to two-thirds of users during the early stages of treatment. With strips or trays, it may start two to three days after you begin and usually resolves by the fourth day after treatment ends.

Several things change how strong it is. The ADA names the concentration of the peroxide, the contact time, and, for light systems, how long and how intensely the light is used. It also notes that a review of in-office whitening found lower peroxide concentrations gave less sensitivity and still gave good color change.

If you feel a sharp twinge, you can stop and wait. The ADA’s MouthHealthy page says you can delay treatment, then try again. Tell your dentist what you felt. The dentist may change the schedule or the product.

What helps with whitening sensitivity?

The honest answer is that research is still limited. The ADA review looked at ideas such as taking an anti-inflammatory medicine before treatment, or applying a gel with potassium nitrate and fluoride beforehand. It concluded that further research is needed to confirm these approaches.

Practical steps are simpler. Follow the directions exactly, do not stretch the wear time, and tell your dentist before you start if your teeth already react to cold. A dentist can pick a lower strength or a shorter schedule. If you have gum irritation, the ADA says it is typically due to poor-fitting trays or improper application, which is another reason to use trays made by your dentist.

Our blog posts on whitening sensitivity and on whether whitening hurts enamel go into more detail.

Can whitening damage my teeth or gums?

Used as directed, mild and temporary effects are the norm. The ADA’s MouthHealthy page does warn that overuse of whiteners can damage tooth enamel or gums. That is why directions matter. Do not whiten more often or longer than the product says.

Gum irritation can also happen. The ADA says it can come from contact with peroxide gels and is typically due to poor-fitting trays or improper application of the protective barrier or gel. Tell your dentist if your gums burn or turn white during treatment.

How do I keep my teeth white after whitening?

Whitening does not stop new stains. The same things that stained your teeth before can stain them again, so cut down on coffee, tea, red wine, and tobacco, or rinse with water after them. Keep up daily brushing, cleaning between your teeth, and regular dental cleanings, which remove surface stain.

Ask your dentist whether touch-ups make sense for you, and how often. Overuse can cause problems, so do not touch up on your own without checking.

What if whitening does not give me the color I want?

Some stains do not respond well to bleach, and some teeth need more than color change. Cleveland Clinic lists stains that do not improve with teeth whitening as one reason people choose veneers. It says veneers and dental bonding can conceal a wide range of cosmetic flaws, including chips, cracks, and discoloration.

These options work differently from bleach. Whitening changes the color of natural enamel. Bonding and veneers cover the tooth. The ADA also says treatment with veneers is not reversible, because enamel is removed to place them. So whitening is usually the gentler step to try first when your teeth are healthy and the stain is the main concern.

Your dentist can show you what each option does and what it needs from you. Our guide on veneers vs bonding compares them side by side.

What should I ask my dentist before I whiten?

A few questions help you get a clear plan:

• What is causing my tooth color, and is it likely to respond to bleach?
• Do I have any fillings, crowns, or veneers that will not change color?
• Which route do you suggest for my teeth: in-office, trays, or store products?
• How should I handle sensitivity if it starts?
• How long should the color last, and what can I do to keep it?
• Do I need a cleaning or any treatment before I whiten?

The ADA says to talk with your dentist before you begin. The conversation is short, and it can save you money on products that do not suit your teeth.

What should I know about whitening products from the store?

Read the label, and follow the directions exactly. The ADA says to look for products with the ADA Seal of Acceptance, which means the product has been tested for teeth whitening. The ADA also says the bleach in these products is weaker than what your dentist uses, so they can take longer.

Be careful with products that promise fast results or that tell you to leave them on longer than the label says. Overuse can damage enamel or gums. If a product causes pain or burning, stop using it and talk with your dentist.

What does whitening cost?

Whitening is a cosmetic service, and insurance rules vary by plan. The practice gives each patient their own estimate. The ADA says store products tend to cost less than dentist options, but they can take longer. See insurance and financing to learn how to ask about your plan.

Next step

Learn how the practice describes whitening on our teeth whitening page. Call Town Center Dental at (636) 273-5866 or request an appointment, and your dentist will talk with you about what to expect.