Research Update—Infection Control

ABSTRACT:

Objective: Hand washing is the most important way to prevent the spread of infection. However, studies have shown that there is a lack of knowledge among physicians about proper hand hygiene. The purpose of this study was to determine the knowledge of general dentists and dental specialists regarding the correct agents to use and the appropriate times to wash hands. Method And Materials: A questionnaire asking for demographic information and the answers to questions about proper hand hygiene practices and agents was sent via e-mail to a list of general dentists and dental specialists. A total of 480 completed surveys were received (approximately 15% response). Results: None of the respondents answered all the questions correctly. Six percent answered 4 questions correctly, 23% answered 3 questions correctly, and 47% answered only 2 questions correctly. There was no correlation between the number of correct answers and whether the respondent was a general dentist or a specialist. Conclusion: There is a lack of knowledge among dentists regarding proper hand hygiene. For the benefit of both the patient and the doctor, this situation must be remedied.

ABSTRACT:

Multiple-use dental bib clips are considered to present relatively low risks for transmitting infections and, thus, are thought to only require disinfection between patient visits. This study was designed to: 1) determine the presence and composition of bacterial contaminants on reusable rubber-faced metal bib clips after dental treatment at the hygiene clinic at Tufts University School of Dental Medicine, and 2) evaluate the effectiveness of the disinfection for this clip type. Aerobic and anaerobic bacterial contaminant loads on the surfaces of the clips were investigated immediately after hygiene treatments were rendered and again after clips were disinfected. The species and strains of bacterial isolates were identified using 16S rDNA sequencing and Human Oral Microbe Identification Microarray analyses. Results demonstrated that some clips retained at least one bacterium on their surfaces after disinfection. Although the bacterial species present on disinfected clips were typical skin or environmental isolates, some were oral in origin. The different bacterial loads on clips suggest that cross-contamination risks may not be the same for all clinics, and that this difference may be related to the type of treatments and services performed.

ABSTRACT:

Autoclaves and UV sterilizers are commonly used to prevent cross-infections between dental patients and dental instruments or materials contaminated by saliva and blood. To develop a dental sterilizer that can sterilize most materials, such as metals, rubbers, and plastics, the sterilization effect of an atmospheric pressure non-thermal air plasma device was evaluated. After being inoculated with E. coli and B. subtilis, diamond burs and polyvinylsiloxane (PVS) materials were sterilized by exposing them to the plasma for different lengths of time. The diamond burs and PVS materials were immersed in PBS solutions, cultured on agar plates, and quantified by counting the colony-forming units. The plasma device was effective in killing E. coli compared with the UV sterilizer. The atmospheric pressure non-thermal air plasma device contributed greatly to the sterilization of diamond burs and PVS materials inoculated with E. coli and B. subtilis. With diamond burs and PVS materials inoculated with E. coli this device was effective after 60 and 90 seconds; for those inoculated with B. subtilis, it was effective after 120 and 180 seconds. The atmospheric pressure non-thermal air plasma device was effective in killing both E. coli and B. subtilis, and was more effective in killing E. coli than the UV sterilizer.