Assessment and quantification of the microbial flora in the output water of two types of dental chairs: A comparative study

Abstract

Objectives: Dental Unit Waterlines (DUWL) have shown to be a perfect host for different pathogenic microorganisms. The purpose of this study was to analyze and compare the level of bacterial contamination in the output water of 2 types of DUWL.

Methods: Dental unit water samples from the air/water syringe of the A-dec (A-dec™ Performer 200, Newberg, USA) DUWL type and KaVo (ESTETICA™ E30/E70/E80 Vision, Kavo, Biberach, Germany) type were collected and analyzed for total aerobic flora, Pseudomonas aeruginosa, faecal coliforms, total coliforms, faecal streptococci and sulfite-reducing anaerobic flora.

Results: The bacteriological analysis of water samples shows the presence of bacterial contamination at high levels exceeding the standard safety guidelines of 100 CFU/mL set up by the American Dental Association (ADA) and accepted by the Centers for Disease Control and prevention (CDC) on the heterotrophic bacterial load. The data shows no statistically significant differences for all bacteriological parameters studied between the conventional A-dec DUWL type and the KaVo type that has an automated mode of decontamination.

Conclusions: Despite all the disinfecting solutions considered to eradicate the bacterial proliferation in DUWL, the problem remains one of the greatest challenges in modern dentistry. Practitioners and medical staff should not underestimate the harmful consequences of this bacterial growth, not only on the health of their patients but also on their own health.