Lasers for Cavity Detection: What You Need to Know

The average American’s tooth enamel is in better shape than ever. This means fewer cavities than ever, too. But strong enamel can make cavities in their beginning stages more difficult to detect. That may sound counterintuitive, but in fact, “the harder enamel is, the more difficult it is for dentists to detect small hidden cavities by poking into suspicious-looking areas with the sharp tip of an explorer, the metal tool traditionally used for diagnosis,” notes Peter Jaret writing for the New York Times. This spells trouble for people with teeth prone to difficult-to-reach trouble spots.

Many dentists are starting to embrace a new approach to detecting tough-to-diagnose cavities: a laser tool that can identify decay and bring greater accuracy to the work of deciding whether a cavity should be watched or filled. Basically, the laser tool sends pulses of light into a tooth. Then, as Brittney Sauser, writing for the MIT Technology Review explains, “light beamed on the tooth is absorbed by chemicals from the decay-causing bacteria that have seeped into areas of mineral loss, and then it’s rereleased at a lower energy. [The laser] measures the change in wavelength; a higher reading means more decay.”

There are some major benefits to this approach to monitoring for tooth decay. This laser technology is much more effective at identifying cavities than x-rays, which only reveal cavities once they’ve had the chance to develop substantially. This means that dentists can fill trouble spots before they develop greater decay, leading to a quicker and, often, less uncomfortable process for patients.

But there are some drawbacks to be aware of, too. Research has demonstrated that this technology can lead to false positives more often than x-rays. For this reason, it’s important that your dentist is using the tool in conjunction with x-rays and visual exams, not relying on it alone to diagnose cavities. In addition, while a wait-and-see approach is often an appropriate response to an area of decay identified by the laser, the use of this technology may prompt some dentists to recommend a filling for an area that might not develop into cavity in the future.

All in all, laser tools are an effective approach to cavity detection, but patients and their dentists should be sure to talk over the options they have for addressing (or keeping an eye on) areas of decay.