Disinfection of Dental Chair Water Using Aqueous Chlorine Dioxide

Li-Lin Wei,Chan-Chih Hu,James R Carey,Chun-Wei Pen,Chu-Wei Hsu,Hao-Chang Yin,Li-Yu Chen,Yu-Chun Yu,Shan-Shue Wang

doi:10.3390/w13233442

Abstract

Chlorine dioxide is a safe, environmentally friendly disinfecting agent. In this study, aqueous chlorine dioxide (ACD) was used to improve the water quality of dental chairs. However, chlorine dioxide is readily released from ACD solutions under open atmosphere conditions. Described herein is a water purification and disinfection system using ACD. The system was designed, fabricated, and integrated into an existing dental chair water system. This system is referred to as an ACD dental chair. Because ClO2 readily degasses from ACD, there needs to be a way to maintain and measure the ACD solution in real time. In our studies, we found that pH and oxidation-reduction potential (ORP) change as a function of chlorine dioxide concentration and are easily controlled and measured. The dosing of the ACD was designed to begin at 800 mV and stop dosing at 810 mV in the ACD dental chair. Through use of this continuous monitoring and automatic dosing system, the water ORP was controlled between 800 and 860 mV. This range is the effective concentration of chlorine dioxide that is without chlorine-like odor and microorganism growth. The ACD dental chair controlled the total bacterial count to <5 CFU/mL and the chlorite concentration was less than 0.0004 mg/L, meeting legal standards of Taiwan, the USA, and China. In addition to the application of ACD in dental chairs, it may also be used in closed water systems for food, cosmetics, beverages, and other industries.

Highlights

Infection prevention when treating oral diseases in dental patients is an important and difficult task
As the biofilm grows to a certain size, bacteria are gradually released into the water, becoming a source of infection [3]
The aqueous chlorine dioxide (ACD) was stored in the dosing unit

Summary

Introduction

Infection prevention when treating oral diseases in dental patients is an important and difficult task. Infection during dental treatment can come from a variety of sources and materials, including equipment and treatment water used in clinical practice [1]. The water sources used during dental treatments is ignored and difficult to manage [2]. The water supply pipeline to the dental chair is usually narrow and difficult to clean. When the clinic is closed, the water in the pipeline is stagnated because the dental chair is not in use. In this situation, bacteria have the opportunity to attach to the water piping walls and initiate cell growth. As the biofilm grows to a certain size, bacteria are gradually released into the water, becoming a source of infection [3]. Unless the water produces a visible suspension or sediment, bacterial contamination is not easy to detect

Methods

Results

Conclusion