The biofilm removal effect of MnO2‐diatom microbubbler on the Dental Prosthetic Surfaces

Abstract

Background: MnO2-diatom microbubbler (DM) is a cylINDIAr-shaped silica diatom with hollow center containing manganese oxide (MnO2) nanosheets. Due to the catalytic activity of MnO2, it can radically convert H2O2 into oxygen (O2) and water (H2O). In the previous study, like a rocket, O2 bubbles emitted from DM generated a significant thrust force to increase kinetic energy of DM, which was great enough to disintegrate Escherichia coli biofilm created on micro-grooved PDMS. Aim/Hypothesis: The aim of this study is to evaluate the effectiveness of MnO2-diatom microbubbler on the surface of prosthetic materials as a mouthwash by comparing the biofilm removal effect with those previously used as a mouthwash in dental clinic. Materials and Methods: MnO2-diatom microbubbler (DM) was fabricated by doping manganese oxide nanosheets to the diatom cylINDIAr surface. Scanning electron microscopy (SEM) was used to observe the morphology of DM and to analyze the composition of doped MnO2. Stereomicroscope was used to observe the reaction of DM in 3% hydrogen peroxide. NO-precious metal alloys, zirconia and resin specimens were prepared to evaluate the effect of biofilm removal on the surface of prosthetic materials. And then Streptococcus mutans and Porphyromonas gingivalis biofilms were formed on the specimens. When 3% hydrogen peroxide solution and DM were treated on the biofilms, the decontamination effect was compared with chlorhexidine gluconate and 3% hydrogen peroxide solution by crystal violet staining. Results: Manganese oxide was found on the surface of the diatom cylINDIAr, and it was found to produce bubble of oxygen gas when added to 3% hydrogen peroxide. For all materials used in the experiments, biofilms of the DM-treated groups got effectively removed compared to the groups used with chlorhexidine gluconate or 3% hydrogen peroxide alone. Conclusions and Clinical Implications: MnO2 was successfully doped on the diatom surface, and MnO2-diatom microbubbler can remove bacterial membranes on the surface of prosthetic materials more effectively than conventional mouthwashes. The use of MnO2-diatom microbubbler as a mouthwash will be more effective in removing biofilms. Acknowledgements: This work was supported by grant no 01-2019-0013 from the SNUDH Research Fund. Keywords: Biofilm, Prosthesis surface, MnO2-diatom microbubbler