April 2, 2013
Study Shows Dentist’s Bib Clips Host Dangerous Bacteria Even After Disinfecting
Brett Smith for redOrbit.com - Your Universe Online
Need another excuse to avoid the dentist? A recent study by researchers at Tufts University School of Dental Medicine found dental bib clips harbor bacteria from the patient, dental clinicians and the environment even after the clips had been disinfected.
"The study of bib clips from the hygiene clinic demonstrates that with the current disinfection protocol, specific aerobic and anaerobic bacteria can remain viable on the surfaces of bib clips immediately after disinfection," said lead author of the study Addy Alt-Holland, an assistant professor from the university´s Department of Endodontics.
"Although actual transmission to patients was not demonstrated, some of the ubiquitous bacteria found may potentially become opportunistic pathogens in appropriate physical conditions, such as in susceptible patients or clinicians."
According to the study, which appeared in Compendium of Continuing Education in Dentistry, standard disinfecting procedures removed the majority of bacteria found on the bib clips immediately after treatment. However, 40 percent of the bib clips tested in the study still had one or more strains of aerobic bacteria, which can easily survive and grow in a dental office environment. The researchers also found 70 percent of bib clips that were tested after disinfection still had one or more type of anaerobic bacteria, which do not survive in the presence of oxygen.
Researchers analyzed the clips on 20 dental bib holders after a standard use. The bib clips were tested for bacteria immediately after treatment (post-treatment clips) and again after the clips were disinfected in the standard manner with alcohol wipes (post-disinfection clips).
A microbiology team led by Bruce Paster, Chair of the Department of Microbiology at the Forsyth Institute, then sampled bacteria from both sets of bib clips. They found oral bacteria were found on 65 percent of the post-treatment clips. After disinfection, 15 percent of the clips still had anaerobic“¯Streptococcus bacteria and five percent of the clips still harbored at least one “¯Staphylococcus,“¯Prevotella and“¯Neisseria bacteria species.
The researchers also found at least one skin-related anaerobic bacteria on 45 percent of the clips that were tested after disinfection.
"The results of our analysis show that there is indeed a risk of cross-contamination from dental bib clips. The previous patient's oral bacteria could potentially still be on the clip and the new patient has a chance of being exposed to infection by using that same bib clip," Paster said.
"It is important to the clinician and the patient that the dental environment be as sterile as possible; thus it's concerning that we found bacteria on the clips after disinfection.
“This situation can be avoided by thoroughly sterilizing the clips between each patient or by using disposable bib holders,” he recommended.
In their conclusion, the researchers said there could be three possible sources of clip bacteria: from the patient's saliva and oral spatter produced during dental treatments, from the hands of dental practitioners, or from the patient's hands.
According to a previous study from Tufts researchers, rubber-and-metal bib clips retain more bacteria than metal-only clips after treatment and before disinfection.