Study Finds No Relationship Between Respiratory Illnesses and Frequent Exposure to Mists from "Dental Aerosols"

SAN DIEGO -- Ever since the dental community learned that water lines supplying their water-cooled drills harbor bacteria, the question of whether breathing in mists spun off by drills causes respiratory illness has been a subject of controversy.

A study by dental researchers from the University at Buffalo School of Dental Medicine, presented here today (March 7, 2002) at the International Association of Dental Research meeting, provides a preliminary answer: Probably not.

The potential health hazards of long-term exposure to "dental aerosols," as these mists of airborne water droplets are called, have been the subject of investigative television programs and articles in popular and professional journals.

However, few attempts have been made to determine if there is a relationship between exposure to dental aerosols and actual illness among a cohort of dental workers. In an effort to identify such a relationship, UB dental researchers called on a ready study cohort -- dental students -- in three dental schools.

"Fourth-year students routinely spend up to 30 hours a week in clinics and first-year students spend none," said Frank A. Scannapieco, D.M.D., Ph.D., UB associate professor of oral biology and senior advisor on the study. "Clinic hours increase in linear fashion through the second and third year, so the hypothesis was that if dental aerosols were a risk, there would be an increase in respiratory illness among dental students by year as their clinic exposure increased."

Scannapieco and Maris Ditolla, a second-year UB dental student, administered a detailed questionnaire to 817 dental students and residents at UB, University of Southern California and Marquette University.

In addition to standard demographic information, participants provided a history of respiratory illness -- chronic obstructive pulmonary disease (COPD), bronchitis, asthma, pneumonia or strept throat -- during the previous year.

"Given that students in the last year of school would have more exposure, we thought that if there was a relationship, it would show up as more illness in the fourth year," said Scannapieco. "We saw no difference between classes and prevalence of respiratory disease."

Alex Ho of the UB Department of Oral Biology, Casey Chen of the University of Southern California and Andrew Dentino of Marquette University also were involved in the study.

The research was funded by a grant from the United States Public Health Service to support dental student research.