After 36 years in private dental practice, Fred Kreutzer, DMD, began struggling to hear. It’s been 5 years since he retired from his practice and Kreutzer now wears hearing aids in both ears.

Although he has a family history of hearing loss, he believes the high-speed tools he worked with 8 hours a day for so many years may have played a role in his hearing troubles.

“I think if you listen to any high-pitched noise for any length of time, it will get to you eventually,” says Kreutzer, an assistant professor in operative dentistry at the Oregon Health and Science University School of Dentistry. “But in my case, with a family history of hearing loss, it may be hereditary, as well.”

Whether high-speed dental tools contribute to long-term hearing loss is the subject of a study currently under way in the OHSU Tinnitus Clinic and the School of Dentistry. According to one of the study’s leaders, Robert Folmer, PhD, associate professor of otolaryngology/head and neck surgery and chief of clinical services at the OHSU Tinnitus Clinic, Oregon Hearing Research Center, published research is mixed about whether high-speed dental tools contribute to noise-induced hearing loss over time.

“Over the years, we have seen dentists in the OHSU Tinnitus Clinic who were convinced that long-term exposure to sound from high-speed hand pieces contributed to their high-frequency hearing loss and tinnitus,” Folmer says. “These anecdotes, in combination with the research being divided about high-speed hand pieces playing a role in hearing loss, prompted our study. We hope the study is a good first step toward scientific evidence behind the anecdotes we’ve been hearing.”

Most of the current high-speed hand pieces, such as high-speed drills and scalers used by dental professionals, are between 90 to 100 decibels, Folmer says. That’s the equivalent of a gas lawnmower or other power tools, which are loud enough to cause hearing loss over time. Hand pieces have gotten quieter over the years with the advent of modern technology, however, very few dental professionals or students interviewed for the study so far wear earplugs to protect themselves from this noise. None of the 54 dental schools nationally are known to require dental students to wear ear protection while treating patients.

[SOURCE: OHSU, August 14, 2006]