Antimicrobial efficacy of self-locomotive manganese oxide nanozyme-doped diatom microbubbler on orthodontic brackets in vitro

Abstract

Background Orthodontic brackets provide a favorable environment for Streptococcus mutans biofilm formation, increasing the risk of white spots and dental caries. Manganese oxide (MnO2) nanozyme-doped diatom microbubbler (DM) is a recently developed material for biofilm removal. DM can generate oxygen by catalase-mimicking activity in Hydrogen peroxide (H2O2) solution and move with ejecting oxygen microbubbles to produce a mechanical self-cleansing effect. This study aimed to evaluate the feasibility of DM as a novel bracket cleaner. Methods DM was prepared according to the protocol and analyzed using a scanning electron microscope (SEM). We treated S. mutans biofilms grown over bracket with phosphate-buffered saline (PBS group), 0.12% chlorhexidine (CHX group), 3% H2O2 (H2O2 group), and co-treatment with 3 mg/mL of DM and 3% H2O2 (DM group). The biofilm removal effect was analyzed using crystal violet assay, and the results were observed using SEM. The viability of S. mutans in remaining biofilms was evaluated using confocal laser scanning microscopy (CLSM). Finally, we examined the effect of all materials on mature multispecies biofilms formed on debonded brackets. Results Crystal violet assay results revealed that the CHX group removed more biofilms than the control group, and the DM group removed biofilms more effectively than the CHX group (p < 0.0001). SEM and CLSM images showed that CHX killed S. mutans but failed to remove most biofilms on brackets. However, DM effectively removed biofilms and mature multispecies biofilms on debonded brackets (p < 0.0001). Conclusions Co-treatment with DM and H2O2 is effective in removing biofilms on orthodontic brackets compared to conventional antibacterial agents.

The potential use of nanozymes as an antibacterial agents in oral infection, periodontitis, and peri-implantitis

“…According to SEM and CLSM images, CHX eradicated S. mutans but was incapable of eliminating the majority of biofilms on brackets. On debonded brackets, DM successfully eliminated biofilms and mature multispecies biofilms [ 130 ] (Fig. 5 ) (Table 3 ).…”

“…B and C By simulating the activity of CAT in H 2 O 2 solution, DM is capable of producing oxygen and moving with the ejection of oxygen microbubbles, thereby creating a mechanical self-cleaning effect. CHX eradicated S. mutans but was incapable of eliminating the majority of biofilms on brackets [ 130 ] …”

“…Under ultrasonic irradiation, Au-TNT could swiftly generate O 2 , thereby alleviating the hypoxic microenvironment of biofilm and enhancing the anti-biofilm efficacy of aSDT [ 128 ] A MnO 2 nanozyme-doped diatom microbubbler (DM) For the eradication of biofilm, a MnO 2 nanozyme-doped DM was recently developed. By simulating the activity of CAT in H 2 O 2 solution, DM can produce oxygen and moving with the ejection of oxygen microbubbles, thereby producing a mechanical self-cleaning effect [ 130 ] …”

Perspectives on Usage of Functional Nanomaterials in Antimicrobial Therapy for Antibiotic-Resistant Bacterial Infections

“…Nanozymes can perform various enzyme-like functions in different areas, such as regulating biomolecular and cellular pathways, cleaving proteins or poly nucleic acids, modulating oxidative balance, and performing site-specific cleavage of prodrugs. , These functions make nanozymes useful in different applications, including therapeutics, regenerative medicine, diagnostics, and preservation. Endogenous enzymes in the cell catalyze metabolic events and produce hazardous ROS that potentially kills the bacterial cell membranes and intracellular components by oxidation . However, natural enzymes have their limits; thus, synthetic nanozymes are increasingly employed in antibacterial therapy as promising alternatives with an antibiotic-free environment.…”

“…Endogenous enzymes in the cell catalyze metabolic events and produce hazardous ROS that potentially kills the bacterial cell membranes and intracellular components by oxidation. 54 However, natural enzymes have their limits; thus, synthetic nanozymes are increasingly employed in antibacterial therapy as promising alternatives with an antibiotic-free environment. Furthermore, nanozymes are not susceptible to acquiring resistance by bacteria because of their biocompatibility and excellent cellular membrane permeability.…”