A dentist was diagnosed with a disease known as idiopathic pulmonary fibrosis, or IPF. It is characterized by progressive scarring within the lungs, and a median survival rate of just three to five years.

But the dentist, right after receiving the news at a specialty clinic in Virginia, placed a call to the Centers for Disease Control and Prevention with a tip: he had noticed that the rare and deadly condition had been diagnosed among multiple dentists and dental personnel at the same clinic over recent years.

The CDC investigated – and they now say there may be a connection between a higher rate of the condition at that tertiary care center,  and among people who work in dentists’ offices.

“This investigation revealed the first described cluster of dental personnel with diagnosed IPF,” write the CDC doctors. “No clear etiology has been identified, but occupational exposures are possible.”

The findings indicate that 894 patients were treated for IPF at the center between 1996 and 2017. Nine of them were male dental workers – eight dentists, and one dental technician, according to the CDC.

The roughly one percent of the clinic’s IPF patients that were known to be dental workers was much higher than the general representation of dentists among the U.S. population, which stood at 0.038 percent in 2016, according to the CDC findings. 

The investigators wondered if there could there be a correlation.

The dentist who had alerted the federal agency to the cluster underwent a phone interview with the investigators. He said that he had never smoked, and did not wear a respirator throughout his 40 years of dental work. But he did wear a surgical mask for the last 20 years. He did polish dental appliances and prepared amalgams and impressions without breathing protection – activities that required the use of silica, polyvinyl siloxane, alginate, and a handful of other substances that are known to have respiratory toxicity.

The dentist also reported being exposed to dust during three months working as a street sweeper prior to his entering dental school; he also was exposed to dust from coral beaches in the Caribbean during 15 years doing intermittent stints as a practicing dentist.

Disease experts said major known IPF risk factors are genetic predispositions, cigarette smoking, and the presence of acid reflux disease and heartburn. Approximately 75 percent of the known IPF patients are male, and almost all are older than 50 at the time of diagnosis.

Immediately after the analysis, another dentist was diagnosed with IPF at the same tertiary clinic, according to the CDC paper. Although no firm conclusions could be drawn from a single clinic, the indications are that some air exposures in dental work may be triggering the fatal disease, they write.

“Dentists and other dental personnel experience unique occupational exposures, including exposures to infectious organisms, dusts, gases and fumes,” write the investigators. “It is possible that occupation exposures contributed to this cluster… Further investigation of the risk for dental personnel and IPF is warranted to develop strategies for prevention of potentially harmful exposures.”