Activity of Ozonated Water in Sterilising and Disinfecting Dental Unit Water Pipelines System: A Comparative Study

A number of disinfectants and sanitisers are used in dentistry, and there are numerous commercial solutions available. Nonetheless, because each cleaning solution has its own set of indications and limits, there is no one-size-fits-all approach for processing all types of dental equipment. Functional water, such as electrolysed hypochlorite microbubbled water, efficiently eliminates and sterilises biofilms. The objective of the study was to evaluate whether ozonated water could be used to sterilise and disinfect dental-unit water pipelines (DUWP) that had been contaminated with micro-organisms, including Gram-positive and Gram-negative bacilli and cocci.

Three different groups were formed: group A - ozonated water (Cantoosh); group B - 1% povidine iodine; and group C: conventional distilled water. Group A was the test group, group B the control group, and group C was the positive control group. The water sterilising system was replaced with the appropriate sterilising agent as per the allocated group classification, with 2 min of purging, so that the complete DUWP was filled with the water sterilising system. Samples were collected and analysed, along with a 2-min purge after 24 h, 7 days and 21 days, at the 3 outlet (OL) points: the 3-way syringe at the dental tray(OL1), the cup filler (OL2), and the 3-way syringe of the assistant zone (OL3). Repeated measures ANOVA was used to test for statistical significance between colony-forming units of control and experimental groups (p < 0.05).

The cup filler yielded higher counts than did the 3-way syringe at the dental tray (OL1) (6.40 and 8.05 on the log scale, respectively). A statistically significant difference in the CFUs was also observed between samples taken after 24 h vs 21 days between groups A, B and C.

The findings showed that exposing DUWP tube systems to ozonated water for an extended length of time drastically lowered the number of microorganisms adhering to their surfaces.