How Long Do White Spots From Whitening Strips Last?

This blog post will address the topic, “how long do white spots from whitening strips last” and cover topics like whitening strips, how they work , what research says about their efficacy, their potential side effects and safety precautions to be taken while using whitening strips.

How Long Do White Spots From Whitening Strips Last?

The white spots from whitening strips are temporary, unharmful and should fade away within a few hours.

The white spots result from loss of water from the tooth enamel after using whitening strips.

What are whitening strips?

Whitening strips are an over-the-counter, very thin and invisible teeth whitening product containing peroxide-based whitening gel.

The strips are applied following the instructions printed on the label.

It takes a few days for the initial results to appear and almost 4 months for the final results.

Whitening strips can be uncomfortable on your teeth and gums if not properly used.

Can Whitening Strips Actually Whiten Your Teeth: What Does Research Say?

A study published in the Journal of Esthetic and Restorative Dentistry investigated the tooth whitening effects of various concentrations of carbamide peroxide (CP) gels and 6% hydrogen peroxide (HP) whitening strips.

The study concluded that carbamide peroxide and hydrogen peroxide containing home-use bleaching systems can achieve considerable tooth whitening outcomes.

The amount of whitening depends on the concentration and duration of exposure, the study reported.

Another new clinical research confirms that teeth whitening strips containing 6.5% hydrogen peroxide are effective in lightening the tetracycline stains when used daily for 1 month.

How do Whitening Strips Whiten the teeth?

Whitening strips contain around 6% of peroxide that helps to whiten the teeth. 

Peroxide is a type of bleach. Most strips contain hydrogen peroxide as their main component but some manufacturers may use carbamide peroxide.

Depending on the product’s peroxide concentration and also exposure time printed on the label, you might have to wear the strips for 30 minutes once or twice a day and repeat the process for 14 days or more as instructed.

Do Whitening Strips Have Any Side Effects?

Yes. Whitening strips do have some minimal side effects and can cause gum irritation and oral discomfort if not used as per instructions on the label.

The severity of side effects depend on several factors:

  • peroxide bleach concentration 
  • how long your teeth are exposed to the whitening strips
  • tooth sensitivity history

It is recommended to read and follow the instructions printed on the label and not to use the whitening strips longer than suggested. 

Some side effects that may result if instructions are not followed as recommended:

Tooth Sensitivity

Teeth whitening strips contain bleaching agents that create micro-pores in the enamel and may reach your dentin causing sensitivity and discomfort by irritating the nerves.

Gum Irritation

If you use your teeth whitening strips for a longer time than recommended or wear them incorrectly, peroxide coating in them may irritate your gums.

However, the gum irritation is temporary and will disappear in a few days after stopping or completing treatment.

Tooth Damage

Tooth damage occurs mostly when the teeth whitening strips are overused, resulting in demineralisation and erosion of the layers of the teeth.

How To Prevent Or Reduce The Side Effects Of Whitening Strips?

Tooth sensitivity and Gum irritation are two common and temporary side effects of teeth whitening strips that disappear within one to three days of stopping or completing the treatment.

Tooth sensitivity usually occurs due to overuse or not proper use of whitening strips. On the other hand, gum irritation is a common cause of ill-fitting trays containing whitening gels.

You can prevent or reduce the side effects of teeth whitening strips by following the below mentioned instructions:

  • Reduce the time of wearing the tooth whitening tray from one 60 minute session to two 30 minute sessions
  • As soon as you notice teeth sensitivity, stop the whitening for 2-3 days..
  • Get a high fluoride-containing product from your dentist or pharmacist and apply it to the tray and wear it for 4 minutes before and after using the whitening agent. This will help remineralize the teeth.
  • Use an anti-sensitivity toothpaste that will help soothe your sensitivity
  • Ensure that you are using a safe whitening product

Correct Way Of Using Teeth Whitening Strips

Read the instructions carefully

Although most whitening strips are applied and used in a similar manner, some brands may have different instructions.

Brush your teeth 30 minutes before applying whitening strips

To avoid trapping any food or bacteria under the strip resulting in poor teeth whitening results. 

Brushing your teeth also allows hydrogen peroxide in the whitener to penetrate your enamel better.

Prepare your strips carefully

Make sure to apply the right strip to the correct location and apply in such a way that the whitening agent contacts the entire surface of your teeth except the gums.

Apply the strips to your teeth after drying out the teeth surface for better results.

Avoid any contact with the gums to prevent discomfort.

Wait patiently till the recommended time printed on the label

Generally, you have to wait for 30 minutes before removing the strips.

Take the strips off after the recommended time and make sure not to keep it for longer than recommended time.

Clean your mouth after using the strips

Try rinsing with water or brushing your teeth to ensure that all the whitening gel is out of your mouth. 

Be cautious not to swallow the whitening agent as it may be toxic.

For best results, eat only after an hour.

Repeat the process

Use twice daily for 30 minutes at a time or as recommended.

Use it once a month after you have achieved your desired shade.

Final results will show up after around 4 months but may also require an in-office treatment by your dentist. 

Caution While Using Teeth Whitening Strips

Don’t Swallow Any Gel From The Strips

Take precaution to not swallow any amount of peroxide. 

If you swallow only small amounts of peroxide, it will pass through the system without causing any toxicity.

Swallowing a considerable amount of peroxide will cause toxicity and may irritate the stomach.

Stop If Sensitivity Occurs

Stop the treatment if sensitivity develops in the gums. 

Sensitivity results due to direct contact of bleaching agent with the gums or overuse of the teeth whitening strips. 

Sensitivity is however temporary and resolves in 2-3 days after stoppage of treatment.

Consult your dentist if sensitivity persists beyond 3 days.

Ask Your Dentist Before Using Any Whitening Product

Consultation with the dentist before starting any procedure is crucial for best results.

Maintain Good Oral Hygiene To Avoid Teeth Staining

Choose An Appropriate Toothbrush

Choosing an appropriate toothbrush is the first and most important step towards toothbrushing. Yet, this is neglected by most of the people.

Toothbrushes with more rounded bristles are soft to your teeth and are considered to be an ideal toothbrush to use. 

Do Not Immediately Brush after Eating Acidic Foods

You must wait for 30 minutes to one hour after consumption of acidic foods and drinks. The acid in the food or drink otherwise may erode the enamel layer and regular habit may cause exposed dentin leading to pain and sensitivity and increased risk of developing cavities.

Use Gentle and Short Strokes When Brushing Your Teeth

Use gentle, short strokes to brush your front teeth and thoroughly clean your mouth without abrading the enamel.

Brush the outside surfaces as well as the back molars and upper areas of your chewing surfaces. Brush the inside surfaces of both top and bottom front teeth by flipping your toothbrush upside down.

Brush your tongue to get rid of any bacteria or plaque.

Use A Fluoride Toothpaste

Fluoride can greatly help achieve oral and dental health by strengthening the tooth enamel, making it more resistant to tooth decay. 

Fluoride reduces the amount of acid produced by the bacteria on your mouth. 

Floss Daily To Get Maximum Benefits Out Of Tooth Brushing

Many people, despite knowing the benefits of flossing daily, just neglect it.

According to a study, flossing is highly effective in reducing the interproximal caries risk. 

Daily floss can help stimulate your gums and reduce plaque leading to lesser inflammation risk.

Consider Mouthwash

Therapeutic mouthwashes, as the name suggests have therapeutic action and control dental conditions like gingivitis, tooth decay and periodontal diseases. They also help remove halitosis.

Therapeutic Mouthwashes contain ADA listed active ingredients such as fluoride, peroxide, essential oils, cetylpyridinium chloride, and chlorhexidine, all regulated by the FDA.

See Your Dentist At Least Twice A Year

It is important to get your oral health checked twice every year with an interval of 6 months between two visits.

Your dentist can help remove calculus and locate cavities and will also be able to spot potential oral health issues, if any, and offer treatment solutions.

Whitening Systems Other Than Whitening Strips

There are several teeth whitening options other than whitening strips:

Whitening Toothpastes

Whitening toothpastes remove surface stains and lighten the tooth color by one shade.

Over-The-Counter Whitening Gels

Whitening gels are peroxide-based gels applied directly to the teeth surface with a small brush. 

Whitening Rinses

Whitening rinses are among the newest whitening products available.

Whitening rinses apart from whitening the teeth, also results in fresh breath and prevention of plaque accumulation.

Tray-based teeth whiteners

Tray-based teeth whitening systems can be purchased either over-the-counter or from a dentist, 

It is similar to a mouth-guard tray but has peroxide as a bleaching agent.


This blog post addressed the topic, “how long do white spots from whitening strips last”. We understood about whitening strips, how they work , what research says about their efficacy, their potential side effects and safety precautions to be taken while using whitening strips

The article outlined some other whitening products available in the market and also mentioned habits to prevent staining of the teeth.

FREQUENTLY ASKED QUESTIONS (FAQs): How Long Do White Spots From Whitening Strips Last

Why Do My Teeth Look More Yellow After Whitening Strips?

Your teeth looks more yellow after whitening strips because when you are whitening teeth using whitening strips, the porosity of the enamel temporarily increases to allow the whitening agent to reach the discolored molecules in the teeth. 

This increase in enamel porosity makes your teeth look more yellow and increases the chances of staining right after you use whitening strips.

Should I Brush My Teeth Before Whitening Strips?

Yes. It is critical to brush your teeth before whitening strips. 

Brush your teeth and then wait for at least 30 minutes before applying whitening strips. 

Applying whitening strips immediately after brushing can irritate your gums and cause discomfort. 

Brushing your teeth before using whitening strips, opens the pores in the teeth and makes your teeth more receptive to the whitening agent present in the whitening strips.

Make sure you use a wet toothbrush without a fluoridated toothpaste or any toothpaste at all, before using whitening strips.

Can you reverse yellow teeth by brushing?

Brushing can help reduce the yellowish discoloration or stain on your teeth by removing the plaque that builds up and leads to yellowish stain.

However, if the yellowing of teeth is due to any intrinsic cause then you may require bleaching or tooth whitening treatments.

It is always better to consult your dentist or dental hygienist for the same.

You must also give up on coffee and tea and drinks and food that cause staining and give up smoking or any form of tobacco.

Are yellow teeth permanent?

No. Yellow teeth can be made whiter by a combination of in-office bleaching with help of dental professionals and at-home self bleaching methods.

There are many reasons for your teeth turning yellow. It may be due to thinning of enamel and dentin due to regular and continuous aggressive brushing, or smoking or tobacco chewing, or staining from tea and coffee, or excess use of fluoride.

How long are teeth porous after whitening?

After whitening, the tooth pores open up and remain porous for about two days. 

The enamel becomes porous and develops micro-porosity allowing dental bleaching agents to reach the stains beneath the surface of your teeth. 

Can naturally yellow teeth be whitened?

Yes, the naturally yellow teeth can be whitened involving both in-office and at-home teeth whitening techniques.

The natural yellow tooth shade will whiten faster in about 1-2 weeks than a tooth with added stains from medication, tobacco, and food that takes almost 4 weeks to whiten.

Other FAQs about Whitening Strips that you may be interested in.

Do I Brush My Teeth After I Use Crest White Strips?

How Long Does It Take For Your Teeth To Get White From Brushing?

Can You Brush After White Strips


  1. Teeth Whitening. (2019)
  1. Healthline. (2020)
  1. Sulieman, Munther, et al. “Tooth bleaching by different concentrations of carbamide peroxide and hydrogen peroxide whitening strips: an in vitro study.” Journal of Esthetic and Restorative Dentistry 18.2 (2006): 93-100.
  1. Kugel, Gerard, et al. “Daily use of whitening strips on tetracycline-stained teeth: comparative results after 2 months.” COMPENDIUM-NEWTOWN- 23.1A (2002): 29-34.
  1. Donly, Kevin J., and Robert W. Gerlach. “Clinical trials on the use of whitening strips in children and adolescents.” Journal of Esthetic and Restorative Dentistry 17.6 (2005): 382-383.
  1. Is Teeth Whitening Safe? (2019)
  1. Teeth Whitening Strips And Dental Health

Was this helpful?

Thanks for your feedback!