The Application of Silver to Decontaminate Dental Unit Waterlines—a Systematic Review

Abstract

The contamination of dental unit waterlines (DUWLs) is a major health concern since it can pose cross-infection risks among dental professionals and their patients. Silver is one of the widely used metals in medical fields due to its superior antimicrobial properties. Silver-based agents have been commercially available for the decontamination of dental unit water currently. This systematic review aims to examine the evidence supporting efficacy and safety of application of silver to decontaminate DUWLs. We performed a search of the peer-review literature of studies in six electronic databases using corresponding search terms. Eligibility was restricted to English-language studies exploring the application of silver to decontaminate dental unit water, e.g., silver-based disinfectants and silver-coated dental waterlines tubing. The search identified 148 articles, and 9 articles that met the criteria were synthesized with qualitative narrative analyses. We observed good evidence of antimicrobial efficacy of silver with hydrogen peroxide on diverse microorganism present in DUWLs. Furthermore, there is insufficient evidence on the application of silver nanoparticles (AgNPs) as an efficient material to control the biofilms in DUWLs. Post-treatment data of either the bactericidal and bacteriostatic effects of silver or AgNPs, especially the actual clinical efficacy of long-term application, are scarce. More high-quality research is needed to resolve the gap on the optimal dosage and treatment options required to control bacterial and biofilm in DUWLs with silver-containing materials.

The importance of biofilm contamination control for dental unit waterlines: a multicenter assessment of the microbiota diversity of biofilm in dental unit waterlines

“…: chlorhexidine, hydrogen peroxide, chlorine dioxide, sodium hypochlorite, and super-oxidized water), and new materials for DUWLs [ 37 , 38 ]. However, all these current measures are inadequate, such as physical measures are unable to remove forming biofilms and chemical disinfections could not remove all biofilms effectively due to resistance to disinfectants of biofilms [ 39 ] as well as DUWL might be damaged by the corroded internal components [ 37 ]. Hence, validated disinfection protocols should be established to control DUWL contamination.…”

Dental unit water content and antibiotic resistance of Pseudomonas aeruginosa and Pseudomonas species: a case study

“…and P. aeruginosa. Furthermore, good evidence of antimicrobial efficacy of silver with hydrogen peroxide on diverse microorganism present in DUWLs was observed but there was insufficient evidence on the application of silver nanoparticles as an efficient material to control the biofilms in DUWLs [28]. Low-concentrated ozonized water is bactericidal against heterotrophic bacteria biofilms and it is not harmful to DUs, and plasma sterilization, which is part of electrochemically activated water, effectively reduces bacterial contamination and reduces biofilms in dental unit waterlines, but both studies are at an experimental phase [29,30].…”

Construction of ZnO/PCL Antibacterial Coating Potentially for Dental Unit Waterlines

“…Furthermore, hybrid materials containing silver ions and hydrogen peroxide are commonly used due to their synergistic effects. However, considering sustainability and safety, the large-scale use of silver-based agents is controversial [13]. Up until now, most studies have focused on the disinfection of dental unit waterlines.…”

“…Silver-based agents, including Ag + compound agents, silver nanoparticles, and silver coatings, have been commonly used for the decontamination of dental unit waterlines. However, considering sustainability and safety, the large-scale use of silver-based agents is still a challenge [13]. The Zn ion, as one of the essential trace elements of the human body, has multiple biological activities and has the advantages of being environmentally friendly, cheap in price, and having low biological toxicity.…”