Study finds link between oral inflammatory diseases, Epstein-Barr virus

A significant percentage of dental patients with irreversible pulpitis and apical periodontitis also have the Epstein-Barr virus, according to an article published in the January issue of Journal of Endodontics.

Although the number of studies examining the role of herpesviruses in oral disease has been increasing, the majority of studies have focused on periodontitis, with no systematic attempt to examine herpesvirus in endodontic patients with varying inflammatory diseases.

Researchers at the School of Dentistry at Oregon Health & Science University, Portland, assessed the presence of human cytomegalovirus, Epstein-Barr virus, herpes simplex virus type 1 (HSV-1) and varicellazoster virus in 82 endodontic patients, including patients with irreversible pulpitis and apical periodontitis, and compared the results with those in 19 healthy patients.

The goal of the study was to determine the potential association of herpesvirus with clinical symptoms, including acute pain and size of radiographic bone destruction.

Using a variety of methods, the researchers found the Epstein-Barr virus DNA and RNA in significantly higher percentages (43.9 and 25.6 percent, respectively) in endodontic patients than in healthy patients (0 percent). They found human cytomegalovirus DNA and RNA in measurable numbers in endodontic patients (15.9 and 29.3 percent, respectively) as well as in healthy patients (42.1 and 10.5 percent, respectively). The researchers found herpes simplex virus DNA in low percentages of endodontic patients (13.4 percent), and they found varicellazoster virus in only one endodontic patient.

Although a previous study examined the incidence of herpesviruses in cases of apical periodontitis, “this is the first time irreversible pulpitis has been analyzed for the presence of herpesviruses and associated with Epstein-Barr virus,” said Curt Machida, PhD, professor of integrative biosciences and the principal investigator.

“The incidence of irreversible pulpitis and apical periodontitis, caused by bacteria and possibly the latent herpesvirus, is painful and can greatly impair the body’s natural immune system,” Dr. Machida said. “Studies such as ours could someday lead to more effective treatments [for] inflammatory diseases of the mouth.”

This research was funded by grants from the American Association of Endodontists Foundation, the Oregon Clinical and Translational Research Institute, the National Institutes of Health’s National Center for Research Resources and the NIH Roadmap for Medical Research.