How long does teeth whitening last? (Professional vs at-home treatments)

Recent years have seen an upward spike in the popularity of teeth whitening treatments. More than 37 million Americans opt for it each year to brighten their smiles, and many dental clinics now find it to be their most in-demand service.¹

A cosmetic treatment, teeth whitening lightens the color of your teeth by breaking down stains or discolorations. The process involves a gel containing an active bleaching agent. Typically, this is hydrogen peroxide or carbamide peroxide. When applied, these agents release free radicals that break down organic compounds, staining the surface of your teeth. This effectively lightens and brightens your teeth.²

But while whitening can deliver dramatic results, it doesn’t last forever. The longevity of a treatment depends on several factors, from the method used to your diet and oral care routine. In this post, we’ll explore how long teeth whitening typically lasts, and what you can do to maintain your brighter smile for as long as possible.

Extrinsic vs Intrinsic Stains

Before we compare how long different whitening treatments last, it’s important to first understand the types of stains and the science behind them. Tooth discoloration generally falls into two categories: extrinsic and intrinsic stains. Knowing the difference is key to choosing the right whitening method and setting realistic expectations for results.

Extrinsic stains affect the outer surface of the tooth enamel. They’re the most common type, usually caused by lifestyle habits such as drinking coffee, tea, or red wine, eating foods rich in color pigments, or using tobacco products. Because these stains sit on the enamel’s surface, they’re usually easier to remove and respond well to most whitening treatments, including over-the-counter products.

Intrinsic stains, on the other hand, are embedded deeper within the tooth, beneath the enamel in the dentin layer. These can develop from internal factors such as natural aging (as enamel thins and dentin shows through), tooth trauma, certain medications like tetracycline antibiotics, excess fluoride exposure, or even genetics. Intrinsic stains are more resistant to treatment and often require professional-grade bleaching agents or advanced dental procedures to lighten effectively.³

Many over-the-counter products are designed for surface-level extrinsic stains, so individuals with intrinsic discoloration may see little to no improvement. Without a proper diagnosis, this can lead to frustration, wasted money on ineffective products, or even overuse that harms oral health. That’s why consulting a dental professional before starting whitening treatments isn’t just advisable - it’s essential.

Comparing Whitening Treatments

Now that we have a good understanding of extrinsic and intrinsic stains, let’s take a look at the different whitening treatments and assess how they perform in terms of effectiveness, longevity, and cost. 

Broadly speaking, whitening methods fall into three categories: 

1. Professional in-office treatments
2. Dentist take-home kits
3. Over-the-counter or OTC products
   

Professional in-office treatments

In-office whitening is widely regarded as the most effective option. Your dentist applies a high-concentration bleaching agent - typically 25% to 40% hydrogen peroxide or carbamide peroxide - and may use oral light therapy to accelerate the process.

A single one to two-hour session can deliver immediate, dramatic results that last one to three years with proper care. The main drawback is cost, with treatments averaging $500 to $1,000.⁴

Dentist take-home kits

Dentist take-home kits strike a balance between effectiveness and affordability. Your dentist creates a custom-fit tray to ensure an even distribution of the whitening gel while reducing the potential for gum irritation. Often, these trays are meant to be worn overnight or for a few hours across a few weeks.

While the concentration of the whitening agent is lower than in-office treatments, it’s stronger than OTC alternatives. Results appear gradually over two to six weeks and typically last six months to two years. Costs range from $150 - $600, depending on the dentist and kit type.⁴

Over-the-Counter or OTC Products

OTC options - such as strips, pens, and whitening toothpastes and whitening mouthwashes - are the most affordable and convenient. Out of all the whitening treatment options, they contain the lowest percentage of whitening agents, which makes them effective for mostly extrinsic, surface-level stains. 

Results vary, often lasting only a few months, and achieving consistency can be challenging. Prices range from as little as $3 to $60, though repeat purchases or subscriptions can add up over time.⁴

Caution: Common Side Effects of Teeth Whitening

Teeth whitening is generally safe when carried out correctly. But, like any dental procedure, it can come with side effects. The most common side effects include:

• Tooth sensitivity: Whitening agents can temporarily make the enamel more porous, allowing the bleaching chemicals to reach the nerve endings in the dentin layer. This often results in sensitivity during or shortly after treatment. The discomfort is usually short-lived and subsides within a few days.
• Gum irritation: If the whitening gel comes into contact with the gums or other soft tissues, it can cause temporary redness, soreness, or mild inflammation. This irritation typically resolves once exposure stops.⁵
  

The above side effects tend to be mild and temporary, but there are ways you can soothe teeth sensitivity after a whitening treatment. For example, you can apply a dental gel to provide relief from oral discomfort, or use teeth-whitening pre-treatments three days prior to your treatment to ensure sensitivity relief. Just make sure these products are scientifically and clinically proven. 

However, it’s worth bearing in mind that the misuse or overuse of whitening products can lead to more serious issues. Excessive use of whitening products, particularly those with high concentrations of hydrogen or carbamide peroxide, can cause:

• The erosion of tooth enamel due to demineralisation or the loss of essential minerals that keep teeth strong
• In severe cases, damage to the tooth’s pulp or nerve

For most people, side effects are manageable and temporary, but they highlight the importance of using whitening products as directed and under professional guidance when stronger treatments are involved.⁵

Aftercare and Maintenance: Maximising the Longevity of Teeth Whitening Treatments

While the type of whitening treatment you choose influences how long your results last, the real difference often comes down to post-treatment care. By adopting the right habits, you can keep your smile brighter for longer and protect your teeth at the same time. 

We recommend the following:

• Practice good daily oral hygiene: A strong oral care routine is the foundation of maintaining a white smile. Brush at least twice a day for two minutes, as per the American Dental Association or ADA’s recommendations, and floss once daily to remove food debris and plaque that can lead to new stains.
• Incorporate teeth whitening products into your oral care routine. These can help remove surface stains before they set.
• Be mindful of your lifestyle choices and what you eat and drink. Limit common staining culprits like coffee, tea, red wine, dark berries, and colas. And if you find it difficult to eliminate them entirely from your diet, consider using a straw to minimize contact with your front teeth. You can also rinse your mouth afterwards to wash away pigments.
• Avoid tobacco products, as they cause deep, stubborn stains and can undo whitening effects quickly.
• Add foods that strengthen your teeth and are whitening-friendly, such as apples, carrots, and celery, which naturally scrub teeth as you chew. Dairy products are also beneficial, as they help strengthen enamel.
• Schedule regular check-ups with your dentist to not only support your oral health but also to monitor and maintain your whitening results.

With the right care, you can extend the results of whitening treatments significantly - sometimes by years rather than months.⁶

Next Steps

If you’re considering teeth whitening, then your first step should be to consult your dentist. They can determine if you even need teeth whitening, causes of discoloration, and recommend the safest and most effective treatment. 

If, however, you prefer trying over-the-counter products, then make sure you opt for those that are clinically proven to be effective. 

PerioSciences’ teeth whitening products are designed to support both immediate results and long-term maintenance. Using advanced formulations enriched with antioxidants and natural ingredients, they help to reduce sensitivity while enhancing and preserving the whitening effect.

When paired with professional dental guidance and a diligent oral care routine, PerioSciences’ whitening products can help you achieve the radiant smile you’ve been looking for–and keep it for years to come.

FAQs

1. How long does teeth whitening last?
   This varies depending on the treatment method, aftercare, and your lifestyle habits. Typically, professional in-office treatments can last between 1 to 3 years, dentist take-home kits can last between 6 months to 2 years, and over-the-counter products can last a few months.
2. How much does teeth whitening cost?
   This will depend on the type and frequency of treatment. Professional in-office whitening can cost anywhere between $500 to $1,000. Dentist take-home kits can cost between $150 to $600. And over-the-counter products can range from $3–$60.
3. Do teeth go back to ‘normal’ or return to their original colour after whitening?
   Eventually, yes. Teeth gradually discolor over time, especially if exposed to staining foods, drinks, or tobacco. Practicing good oral hygiene and using whitening oral care systems can help prolong the results.

References

1. Novak, Sarah. When is too much teeth whitening harmful to oral health? Scientific American.
2. Teeth whitening, NHS.
3. Kahler B. Present status and future directions - Managing discoloured teeth. Int Endod J. 2022 Oct;55 Suppl 4(Suppl 4):922-950. doi: 10.1111/iej.13711. Epub 2022 Mar 8. PMID: 35188275; PMCID: PMC9790475.
4. Karina Irusa, Islam Abd Alrahaem, Caroline Nguyen Ngoc, Terence Donovan, Tooth whitening procedures: A narrative review, Dentistry Review, Volume 2, Issue 3, 2022, 100055, ISSN 2772-5596,https://doi.org/10.1016/j.dentre.2022.100055.
5. Epple M, Meyer F, Enax J. A Critical Review of Modern Concepts for Teeth Whitening. Dent J (Basel). 2019 Aug 1;7(3):79. doi: 10.3390/dj7030079. PMID: 31374877; PMCID: PMC6784469.
6. Middleton, A. Tooth whitening versus stain removal. BDJ Team 4, 17175 (2017). https://doi.org/10.1038/bdjteam.2017.175.