The effectiveness of the "Clean-Area-System" for infection control in the dental clinic.

The use of effective infection control procedures and universal precautions in dental clinics, prevents cross contamination that could extend to dental health care workers and patients. The present study was initiated to investigate airborne environmental contamination in the dental clinic by viable cell count of oral streptococci grown on Mitis-Salivarius and blood agar plates. The reduction of the contamination by the "Clean-Area-System" was evaluated. "Andersen-Microbe-Sampler-Apparatus" and "Laser-Particle-Counter-System" were used for sampling and counting the bacterial cells and airborne dust, respectively. Numbers of viable cells counted as total colony forming units (CFUs) in the dental clinic were found to be significantly higher than those in the waiting room and the research laboratory. We found that the "Clean-Area-System" significantly reduced the CFUs grown on blood agar plates (p < 0.05), and that using the "Clean-Area-System" combined with the "Extra-Oral-Vacuum-Aspirator" is desirable in dental procedures such as cavity preparation. The "Extra-Oral-Vacuum-Aspirator" reduced airborne environmental contamination during tooth cutting and ultrasonic scaling procedures. In non-grinding procedures, this system proved to be very useful for infection control in the operative area. The authors concluded that the combined use of "Clean-Area-System" (dust collection ablation) and "Extra-Oral-Vacuum-Aspirator" (absorb dust ablation) was effective to reduce airborne environmental contamination in the dental clinic. We also fully confirmed that oral streptococci were an adequate indicator in the assessment for infection control in dental institutions.