Evaluation of the antibacterial activity of a conventional orthodontic composite containing silver/hydroxyapatite nanoparticles

Abstract

BackgroundOne of the most important complications of fixed orthodontic treatment is the formation of white spots which are initial carious lesions. Addition of antimicrobial agents into orthodontic adhesives might be a wise solution for prevention of white spot formation. The aim of this study was to evaluate the antibacterial properties of a conventional orthodontic adhesive containing three different concentrations of silver/hydroxyapatite nanoparticles.MethodsOne hundred and sixty-two Transbond XT composite discs containing 0, 1, 5, and 10 % silver/hydroxyapatite nanoparticles were prepared and sterilized. Antibacterial properties of these composite groups against Streptococcus mutans, Lactobacillus acidophilus, and Streptococcus sanguinis were investigated using three different antimicrobial tests. Disk agar diffusion test was performed to assess the diffusion of antibacterial agent on brain heart infusion agar plate by measuring bacterial growth inhibition zones. Biofilm inhibition test showed the antibacterial capacity of composite discs against resistant bacterial biofilms. Antimicrobial activity of eluted components from composite discs was investigated by comparing the viable counts of bacteria after 3, 15, and 30 days.ResultsComposite discs containing 5 and 10 % silver/hydroxyapatite nanoparticles were capable of producing growth inhibition zones for all bacterial types. Results of biofilm inhibition test showed that all of the study groups reduced viable bacterial count in comparison to the control group. Antimicrobial activity of eluted components from composite discs was immensely diverse based on the bacterial type and the concentration of nanoparticles.ConclusionsTransbond XT composite discs containing 5 and 10 % silver/hydroxyapatite nanoparticles produce bacterial growth inhibition zones and show antibacterial properties against biofilms.

Green Synthesis of Silver Nanoparticles Combined to Calcium Glycerophosphate: Antimicrobial and Antibiofilm Activities

“…The addition of CaGP to produce AgNP-CaGPs did not interfere with the reduction process of the Ag + ions. Sodagar et al also synthesized a novel compound containing AgNPs and hydroxyapatite and similarly did not observe interference of the calcium compound in the production of the nanoparticles [47].…”

Current Approaches for Exploration of Nanoparticles as Antibacterial Agents

“…Both standardized and modified microdilution and macrodilution methods have been applied to the determination of MIC and MBC values to evaluate the antimicrobial susceptibility of several microorganisms to nanoparticles [76,109,[110][111][112][113][114][115][116]. Additionally, resazurin staining assay has been employed to determine the MIC.…”

“…Agar disk diffusion tests performed both according to the standardized protocols and with modifications are frequently used for susceptibility assessment and evaluation of antimicrobial activity of nanoparticles [109,[121][122][123][124]. Paper disc method has been employed as an alternative to standardized single disk method [112].…”

“…Even though measurement of optical density is a straightforward method, it is not the most suitable for measuring the activity of nanoparticles because nanoparticles as such can also interfere with the optical density [46,127]. Viable plate counts have been frequently performed according to the various protocols to assess the antimicrobial efficacy of nanoparticles against both planktonic and biofilm-growing bacteria [109,128,[110][111][112]116]. Samples can either be spread or pipetted on agar plates followed by overnight incubation and determination of the number of CFUs [116,111,[113][114][115].…”

Biosynthesis and application of silver nano-biotics for enhancing the antimicrobial activity of glass-ionomer cement against studied microorganisms and its effect on compressive strength

“…Studies have shown, AgNPs synergize the e cacy of antibiotics like amoxicillin, clindamycin, vancomycin and penicillin G against various microbes [13,14]. Because of its antimicrobial activity and synergizing effects, researchers have studied the use of AgNPs in several areas of dentistry which include dental biomaterials [15][16][17], dental implants [18], orthodontic adhesives [19] etc. In vitro studies have shown, addition of AgNPs in to dental restorative materials inhibit growth of common oral microbes like Streptococcusmutans, Streptococcus sanguinis,and Lactobacillus through bactericidal and bacteriostatic effects of AgNPs on oral microbes [16,20] without altering its mechanical properties [21].…”