
Surveys indicate an estimated 34% of adults in the U.S. are dissatisfied with their tooth color. That’s not surprising since the majority of people desire a healthy white smile. Regardless of the cause, discolored or stained teeth can cause a hit to your self-confidence, make you feel too embarrassed to smile, and even negatively impact your relationships.
If you’re looking for teeth whitening that offers consistent, predictable, and easy-to-maintain results, it’s important to consult a dentist like Dr. David Sabourin who has a proven track record of whitening teeth with professional and safe teeth whitening methods.
In this article, we will review the basics of tooth whitening and how it works so that you can determine if it’s the right treatment for you.
Table of Contents
What Causes Tooth Discoloration?

Many things can cause stained teeth and a loss of natural luminosity. Tooth discoloration can be extrinsic, intrinsic, or a combination of both.
Extrinsic Stain Facts
- Extrinsic dental stains are the most common type of tooth discoloration and involve staining that only impacts the tooth enamel layer.
- Aging causes enamel to thin out, thereby partially exposing the dentin layer, which makes teeth appear yellow.
- Colorless nicotine in tobacco turns yellow when it’s exposed to oxygen, thereby causing enamel to look yellow, while dark tar leaves brown stains.
- Many beverages and foods can cause discoloration, including coffee, tea, dark-colored fruit juices and cola, red wine, balsamic vinegar, soy sauce, tomato-based sauces, and berries.
Intrinsic Stain Facts
- Intrinsic stains occur beneath the tooth surface and are caused by stain-causing particles infiltrating the outer layer of teeth and accumulating in the enamel.
- Prior to eruption, exposure to high levels of fluoride, tetracycline or other drugs, inherited developmental disorders, and gum trauma can cause intrinsic discoloration.
- After eruption, specific pharmaceutical disease treatment and dental pulp infection are the most common causes of this type of discoloration.
Different Types of Teeth Whitening Methods

Prior to getting your teeth whitened, it helps to learn about the different methods and their respective pros and cons. Options include over-the-counter (OTC) remedies and in-office and at-home professional teeth whitening provided by your dentist. Keep in mind that even professional teeth whitening solutions aren’t created equal.
Although over-the-counter (OTC) products are generally safe when used as directed to reduce surface-level stains only, multiple applications can result in gum sensitivity and potential damage to tooth enamel.
- The majority of OTC options only contain 3–4% of hydrogen peroxide, while professional options have 25–40%.
- Even whitening strips tested by the American Dental Association for safety and efficiency can take weeks or even months to produce results, and the whitening effects are often minimal.
How Teeth Whitening Works

Most types of professional tooth whitening require two in-office visits. At your first appointment, impressions are taken that are used to create the customized whitening trays. In-office treatment can take as little as an hour, not including the prep session, while at-home trays can take a few weeks.
Regardless of the brand, most professional teeth whitening options work in a similar manner. Because enamel is porous, high levels of hydrogen peroxide in these solutions can penetrate it and get into the dentin layer.
- Oxygen molecules in professional whitening agents reduce tooth stains on a molecular level, making them far more effective than (OTC) products.
- In both the enamel and dentin layers, hydrogen peroxide triggers an oxidation reaction that breaks the bonds of discolored molecules to destroy staining compounds and restore natural white tooth color.
- Some methods use an LED light to activate the gel and expedite the whitening process.
Among the most popular professional tooth whitening brands are Zoom!Ⓡ Teeth Whitening, KöRⓇ Whitening, and Opalescence™. Each of these brands tout proprietary ingredients that are effective at removing both extrinsic and intrinsic stains and also offer multiple whitening products. In a nutshell, this is how these whitening solutions work:
Zoom! Teeth Whitening: Blue LED light-accelerated technology and whitening gel are used to achieve rapid whitening results. A thin layer of hydrogen peroxide is dissolved over the top of your tooth enamel, then the LED light is applied, thereby releasing oxygen that flushes out tooth discoloration.
KöR Whitening: Featuring a dual-activated, patented formulation and delivery system, this brand produces whitening results—without chemical stabilizers, lights, or lasers. KöR -Seal™ trays are designed specifically to seal whitening gel in the trays, while sealing out saliva and sulcular fluid that interfere with the whitening process.
Opalescence: These whitening gels contain a safe and highly effective patented bleaching formula with potassium nitrate and fluoride. The active ingredients infiltrate teeth to oxidize discolored molecules deep down, thereby removing stains and whitening your smile.
Expected Outcomes of Teeth Whitening

If you’re considering teeth whitening, knowing what to expect can help you select the best option to meet your unique needs. In-office whitening can be accomplished much faster than at-home trays, but some patients prefer whitening in the convenience of their own home.
This is the expected outcome for in-office professional whitening for the brands discussed in this blog:
- Zoom can lighten teeth by eight shades in just 45 minutes, excluding prep time
- KöR can whiten teeth by up to 16 shades in one to two hours
- Opalescence can brighten smiles in two or three 20-minute treatments
In general, professional teeth whitening treatment can last up to three years. To keep your teeth whiter and brighter longer, limit or avoid highly pigmented foods and beverages, avoid smoking, and practice good oral hygiene. You should brush your teeth twice daily with a gentle whitening toothpaste, floss once daily, and visit your dentist twice a year for a professional teeth cleaning.
Teeth Whitening Safety
Like other cosmetic dentistry treatments, tooth whitening can cause minor discomfort. The precise reason tooth whitening products cause sensitivity isn’t known. The theory is that as peroxide bleaches away stains, it also causes slight demineralization that makes teeth more porous and prone to sensitivity. Higher concentrations of hydrogen peroxide can also irritate your gums.
Some people who undergo teeth whitening experience sensitivity for up to a month after their procedure. Sensitive teeth, gum recession, cracks in teeth, or faulty restorations increase the risk of prolonged sensitivity.
With in-office whitening, gingival protection gel is used to protect your gums and soft tissue from chemical agents in whitening treatments. After treatment, toothpaste or mouthwash specifically designed for sensitive teeth can alleviate sensitivity.
KöR teeth whitening gels contain zero chemical stabilizers. From the moment they’re manufactured until they’re placed on teeth, KöR whitening gels are refrigerated to prevent unstable chemicals from degenerating and losing potency. KöR also uses desensitizers that plug tooth enamel pores during whitening to prevent any feelings of sensitivity.
Zoom and Opalescence offer desensitizing gels that provide quick and effective sensitivity relief.
Speak to a Specialist like Dr. Sabourin
Everyone deserves long-lasting pearly whites that show off their natural smile beauty! To start your journey to a whiter, brighter smile, schedule a cosmetic dentistry consultation with Dr. Sabourin.