Lasers in Dentistry
When lasers were invented in the 1960s, innovators around the world began dreaming up different ways they could use the technology to improve our way of life. Now, almost six decades later, scientists could be on the cusp of transforming the dental industry as we know it, according to a recent article from Medical Xpress. Not only can today’s lasers safely and painlessly remove cavities and cut soft tissue without bleeding, but they now have the ability to prevent cavities before they even start.
According to the Centers for Disease Control and Prevention, more than 91% of adults aged 20 to 64 have cavities, giving the prospect of painless cavity repair and prevention astronomical potential. And their use could be coming to a dentist near you sooner than you think. Peter Rechmann, DMD, PhD, and professor of preventive and restorative dental science at the UCSF School of Dentistry has spent several decades working in laser dentistry. He believes that these lasers, which are especially appealing to young patients who are nervous about the drill, will be coming to market as more and more clinical data on their benefits is available.
Known as short-pulsed carbon dioxide lasers, the tool delivers just the right wavelength in microsecond pulses to alter the chemical composition of teeth enamel, making it stronger. The heat given off from the laser can change the top layer of enamel from carbonated hydroxyapatite to hydroxyapatite, making it more resistant to acid produced by cavity causing bacteria.
In a 2012 clinical study, Rechmann’s team proved that laser treatment could even promote the remineralization of teeth when combined with a fluoride varnish, reversing damage that had already been done. The team used the laser to treat molars on one side of the mouths of 20 participants, leaving the other side as controls. All the teeth were treated with fluoride varnish. A year later, teeth that had been laser-treated had fewer signs of decay than at the beginning of the study.
“Whenever you put a filling inside a tooth, you weaken it,” said John Featherstone, PhD, dean of the School of Dentistry. What lasers can do now is to “protect and save the natural integrity of the tooth,” and that “has been a dream of many of us,” he added.
Featherstone was one of the first to work in preventive laser dentistry in the 1980s when he was at the Eastman Dental Center in Rochester, NY. With his background in physical chemistry, he was able to explain what the dentists in the 1960s could not. He saw that early lasers had produced a melting effect when tested on teeth.
“When I looked at that, I knew exactly what the problem was,” he said.
Because those lasers were not tuned to the molecular vibrations of the calcium phosphate crystals, they had to use 10,000 times more energy than necessary, causing major damage to the tooth. A laser that was tunable to the right wavelength was necessary.
“From there we developed the hypothesis that we could change the solubility of the enamel and make it more resistant to cavities,” Featherstone explained.
It took the collaboration with laser physicists to develop a laser that could heat the tooth enamel for just a few microseconds to stabilize the crystals, without heating the underlying tissue. Lasers were also being studied to cut soft tissue and to remove cavities in place of a drill. The work went on for many years.
In 1995, Featherstone moved to UCSF and built a team that included Rechmann and Daniel Fried, PhD, professor of preventive and restorative dental science, to continue the work.
Despite several decades of promising research, fewer than 10% of dentists currently use lasers in their practice, and those who do use them primarily for soft tissue surgery. The biggest hurdle has been the lack of high-quality, user-friendly commercial laser availability, but that could be changing.
Rechmann is embarking on a large clinical study of preventive laser dentistry and working with a Boston company that has built state-of-the-art lasers based on his team’s research. It is his belief that laser dentistry will soon be available to many more patients. Currently, lasers have been approved for cutting teeth and soft tissue by the Food and Drug Administration. The next step will be to seek the same approval for using the short-pulsed carbon dioxide laser in cavity prevention.
Most people think that laser dentistry sounds very futuristic, but according to Featherstone, “the future is already here.”