Whitening strips
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- Crest 3DWhitestrips Professional kit. Best for: A full at-home course. See options on Amazon
- Crest 3DWhitestrips Sensitive. Best for: Teeth that get sensitive with whitening. See options on Amazon
- ADA Seal whitening strips. Best for: Shoppers who want an independently reviewed product. See options on Amazon
Why teeth lose their whiteness
The ADA's MouthHealthy site names several causes. Coffee, tea and red wine are major staining culprits. Tar and nicotine in tobacco create stubborn stains. Over time, the outer enamel gets thinner with brushing and more of the yellowish dentin shows through. A tooth hit in an injury may also change color.
Whitening products contain one of two tooth bleaches, hydrogen peroxide or carbamide peroxide, according to MouthHealthy. The ADA says most whitening strips rely primarily on peroxide to bleach teeth.
Your whitening options
| Option | How it works, per the ADA |
|---|---|
| In-office (chairside) bleaching | Usually requires only one office visit |
| Dentist take-home trays | A custom-made tray for at-home whitening |
| Over-the-counter strips and gels | Lower bleach concentration than a dentist would use in the office |
| Whitening toothpaste | Mild abrasives that scrub away surface stain |
Details are from the ADA's MouthHealthy teeth whitening page. The ADA says its Seal of Acceptance program covers some over-the-counter products, including toothpastes and whitening strips, and that a product with the Seal has been tested to be safe and effective for teeth whitening.
How to use whitening strips
Crest describes these steps for its 3DWhitestrips:
- Peel the plastic liner off the gel side. Crest notes most instructions say not to brush just before applying, to help the strip stick.
- Apply the gel side to your teeth, aligned with your gum line, press for good contact, and fold the rest behind your teeth.
- Wear for the time on your package. Crest says this is likely to range from 5 minutes to 60 minutes, and some products are worn once a day while others twice.
- Remove the strips and throw them away.
As examples, Crest says to apply its Professional White strips for 45 minutes a day for 20 days, and its Sensitive and Gentle strips for 30 minutes a day over 14 days.
Some kits add a light. If yours includes Crest's LED Accelerator Light, Crest says to wear the strips for the full time, then hold the light against your teeth until it turns off, about five minutes. Its Sensitive and Gentle kit includes 28 strips, 14 for the top teeth and 14 for the bottom.
Sensitivity and gum irritation
The ADA says temporary tooth sensitivity and gum inflammation are the most common side effects of whitening. MouthHealthy explains that sensitivity happens when the peroxide gets through the enamel, that in most cases it is temporary, and that you can delay treatment and try again.
- Do not overuse. MouthHealthy warns that overuse of whiteners can damage tooth enamel or gums; follow the directions.
- Consider a sensitive formula. Crest says its Sensitive and Gentle strips are formulated to be gentle on teeth that may be sensitive to whitening.
- Place strips carefully. Align each strip with your gum line, as Crest directs.
What strips cannot whiten
MouthHealthy says whitening will not work on caps, veneers, crowns or fillings, and the ADA says only natural teeth can be whitened, not tooth-colored restorations, since restorative materials generally do not change color. If you have visible dental work, ask your dentist how it will look next to whitened natural teeth.
The ADA supports educating the public on the need to consult a licensed dentist to decide whether whitening is appropriate for you.
Keeping results and your routine
- Rinse after staining drinks. Crest suggests rinsing your mouth as soon as possible after foods or drinks that stain, and sipping some drinks through a straw.
- Keep brushing and flossing. See our electric toothbrush guide and dental floss guide.
- Clean your tongue too. See our tongue scraper guide.
- Comparing toothpastes? See our hydroxyapatite toothpaste guide.
What to look for when you buy
Crest 3DWhitestrips Professional kit
Best for: A full at-home course
Crest lists 40 strips for 20 days, worn 45 minutes a day, in its Professional White kit.
Watch out: Stop and talk to your dentist if sensitivity is a problem.
See options on AmazonCrest 3DWhitestrips Sensitive
Best for: Teeth that get sensitive with whitening
Crest says its Sensitive and Gentle strips are formulated for teeth sensitive to whitening, worn 30 minutes a day.
Watch out: Sensitivity can still happen; you can pause and try again.
See options on AmazonADA Seal whitening strips
Best for: Shoppers who want an independently reviewed product
The ADA says strips with its Seal have been tested to be safe and effective for teeth whitening.
Watch out: Check the Seal on the package itself, not just the listing.
See options on AmazonQuestions people ask
- Do whitening strips damage enamel?
- MouthHealthy says overuse of whiteners can damage enamel or gums, so follow directions and talk to your dentist.
- Why do my teeth hurt after whitening strips?
- Peroxide can get through the enamel; MouthHealthy says sensitivity is usually temporary and you can pause, then try again.
- How long do you leave whitening strips on?
- It depends on the product; Crest says from 5 minutes to 60 minutes.
- Do whitening strips work on crowns or fillings?
- No. The ADA says only natural teeth can be whitened, not tooth-colored restorations.
- Should I brush before using whitening strips?
- Crest says most instructions advise not brushing just before applying, to help strips stick.
Sources
- Teeth Whitening (mouthhealthy.org), American Dental Association MouthHealthy
- Whitening (ada.org), American Dental Association
- Step-by-Step Crest 3DWhitestrips Instructions (crest.com), Crest
- Crest 3DWhitestrips Professional White At-Home Teeth Whitening Kit (crest.com), Crest
- 3DWhitestrips Sensitive and Gentle + Whitening Light At-Home Teeth Whitening Kit (crest.com), Crest