If you take a look around the toothpaste aisle of any drugstore in the United Stated, it's not hard to see that Americans have become obsessed with obtaining pearly white teeth. In fact, a study in 2013 found that almost 90 percent of orthodontists nationwide have had patients who specifically requested tooth whitening treatments. But between mouthwashes, toothpastes, and even chewing gums that claim to give you that smile you've always wanted, how do you know what really works? If you break it down, there are two types of discoloration: stains on the surface of the teeth and those below the enamel. The first are mostly caused by smoking and the absorption of food or beverages on the enamel surface. The others are related to the optical properties of the enamel and the underlying dentin, and how they interact with light. A number of things, including tooth decay, excessive fluoride ingestion, and aging can alter the intrinsic color of your teeth. So how do you remove the stains and get below the enamel? We talked to Dr. Gerard Kugel, a dentist at the Boston Center for Oral Health and Dr. Gianluca Plotino, a private-practice dentist in Rome to get to the truth.
Over-the-counter strips, gels, and tray systems
Medicated adhesive strips are one of the most popular over-the-counter whitening systems available today. Numerous clinical trials have shown that these strips, which usually contain hydrogen peroxide, can effectively remove intrinsic stains and make teeth six to seven shades brighter, according to Dr. Kugel. "We've done tons of studies, and if it didn't work for someone, I would predict that the patient wasn't using it right, " he says. In one study, Kugel found that Crest Whitestrips are comparable to an in-office whitening treatment. Over-the-counter paint-on gels and tray-and-gel systems, which employ hydrogen peroxide or carbamide peroxide, can also whiten teeth, if used correctly. However, each system has its downsides: Strips may be hard to keep in place; paint-on gels can be difficult to use and may become diluted with saliva; and trays, which aren't custom made, sometimes fit poorly, allowing the gel to seep out or saliva to seep in. "They may work effectively, [but] because they are not dentist monitored, many of them won't work for everyone, " says Dr. Plotino.Credit: Getty Images