Efficacy of Sterisil in the treatment of dental unit waterlines

Introduction: Dental unit waterlines (DUWL) are an ideal home for bacterial microorganisms to grow, multiply, and develop complex living colonies commonly known as "biofilm." The American Dental Association (ADA) and the Centers for Disease Control and Prevention (CDC) have recommendations to maintain DUWL heterotrophic plate count bacteria levels below 500 colony forming units per milliliter (CFU/ml) of water. The aim of this study is to determine whether Sterisil PureTube is able to control the bacterial load in the orthodontic clinic to recommended levels.;Methods: Waterline samples from the twelve dental chairs in the orthodontic clinic were used in this study. These chairs are isolated from the municipal water system and have historically used distilled water as a supply source of water. After a two-minute flush of the DUWL, 40 ml water samples were collected in sterile 50 ml tubes from the air-water syringe on each of the dental units. Sampling was performed on Monday's before the start of the clinic day. Samples were grown on R2A Agar plates and processed in accordance with the standard heterotrophic plate count method outlined by the American Public Health Association (Standard Methods). Baseline waterline samples were collected and analyzed. Six of the dental units were then randomly selected and converted to the Sterisil PureTube and Antimicrobial Bottle (Sterisil, Castle Rock, CO). The other six chairs served as a control group. All twelve chairs were then supplied with the same source of distilled water. Three months later, samples were collected and analyzed using the same protocol as baseline collection. The results were statistically analyzed using a mixed model ANOVA (p<0.0004).;Results: Baseline DUWL samples showed plate counts approximating 240,000 CFU/ml. After treatment with Sterisil PureTube and Antimicrobial bottle the samples showed plate counts of 0 CFU/ml. While the control group of untreated chairs increased to over 300,000 CFU/ml.;Conclusions: Sterisil PureTube and Antimicrobial bottle effectively reduced the bacterial counts in the DUWL samples.