Green synthesis and application of silver nano-biotics for enhancing the antimicrobial activity of glass-ionomer cement against dental biofilm and its effect on compressive strength
Abstract Background. The development of dental caries is associated with various microorganisms and secondary caries formation is the main cause of their failure. The urge for restorative dental materials that have antimicrobial properties has stimulated the introduction of materials containing different antibacterial agents. Objectives Present study has been designed to synthesize silver nanoparticles (AgNPs) and incorporate AgNPs and amoxicillin into glass ionomer cement (GIC) to synergize its effect on oral microbes. The effect of the added antimicrobial agents on compressive strength of GIC was also evaluated. Material and methods Biosynthesis of AgNPs was done using Cupressus macrocarpa extract and AgNPs were charectatrized. A total of 120 disc-shaped specimens were prepared and classified into 4 main groups where Group A include conventional GIC, Groups B and C include GIC with AgNPs or Amoxicillin, respectively, while Group D included GIC with both AgNPs and Amoxicillin. Each group was tested for the antimicrobial activity. The distribution of biofilm was examined via scanning electron microscope. Compressive strength (CS) of the tested material was measured using a Material Test System (MTS). Results UV-Visible spectrum showed a peak of 429 nm.TEM, XRD pattern and FTIR analysis confirmed the formation of AgNPs with spherical to oblong polydispersed particles of diameter in the range of 13.5–25.8 nm. The maximum inhibitory zone was recorded for group D against both Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus) bacteria with a mean of 29 mm at first 24-hour period to 15 mm at three weeks and showed antimicrobial rate 92.2% and 92.56%, against both strains, respectively. Additionally, group D disintegrated the structure of S. aureus biofilm and even kill bacteria in the biofilms. Addition of AgNPs and Amoxicillin caused insignificant effect on compressive strength of GIC. Conclusion Cupressus macrocarpa extract biosynthesized AgNPs showed a synergistic effect in combination with amoxicillin and GIC dental restorative material against dental biofilm. The agents can be safely added without impairing mechanical properties of the set cement.