How Does Professional Teeth Whitening Work and How Long Does It Last?

September 13, 2024

Professional teeth whitening is one of the most popular cosmetic dentistry procedures, and for good reasons. Whiter teeth can improve your appearance and confidence by removing stubborn stains that can dull your smile.

But how exactly does a professional teeth whitening work, and how long do the results last? Here, we review the science behind teeth whitening and how long patients can expect their bright smiles to last.

The Science of Professional Teeth Whitening

In a professional teeth whitening procedure, dentists use potent whitening agents that effectively penetrate the enamel to lighten the color of teeth. These whitening agents create a chemical reaction that lightens stains and improves the overall color of your teeth [1].

There are two main professional whitening methods:

In-office whitening. This method involves applying a concentrated whitening gel directly to the teeth. The gel usually contains hydrogen peroxide or carbamide peroxide as the active ingredient. To enhance the effectiveness, many dentists use a special light or laser to activate the gel, allowing for deeper penetration of the solution into the tooth [2]. The procedure typically lasts about an hour, and patients see immediate results.
Take-home whitening kits. Some dentists also provide custom-made trays and a lower-concentration whitening gel to patients, allowing them to whiten their teeth at home. The trays fit snugly over the teeth and are typically worn for a certain amount of time each day. Although the results may take longer than in-office treatments, this method can be effective and convenient for many patients.

Before you get your teeth whitened, your dentist will thoroughly clean your teeth to reveal their true shade. This allows you to determine how much whiter you’d like your teeth and your dentist to see where stubborn stains are for a more tailored approach to teeth whitening.

How Long Does Professional Teeth Whitening Last?

How long your professional teeth whitening will last depends on several factors. Most patients can expect their brighter teeth to last anywhere from six months to two years. What factors determine how long your results will last?

Tooth staining. People with intrinsic stains—those that occur from inside the tooth—may find that their results fade more quickly than individuals with extrinsic stains caused by surface factors [3].
Oral hygiene. Regular brushing, flossing, and dental cleanings play a crucial role in maintaining a white smile. Good oral hygiene helps prevent the buildup of new stains.
Your diet. Foods and beverages that stain teeth, including coffee, tea, red wine, and dark-colored fruits, can stain newly whitened teeth faster.
Tobacco use. Tobacco is notorious for staining teeth. If you smoke or use tobacco products after whitening, your results will fade faster.

Many people have their whitened teeth touched up over time to maintain a bright smile. Your dentist can advise you on best practices to help your results last as long as possible.

Ask Your Dentist About Professional Teeth Whitening Today

Professional teeth whitening is a safe and effective procedure that can dramatically transform the appearance of your smile. If you’ve been considering getting your teeth whitened, ask your dentist about your options for a brighter smile during your next appointment!