Evaluating the effect of antimicrobial agents against Enterococcus faecalis on poly methyl methacrylate (PMMA) resin made by 3D printer

Abstract

Introduction:PMMA resin is one of the most common structural materials used to prepare temporary veneers during prosthetic treatments. The adhesion of microorganisms to the surface of the prosthesis and the formation of biofilm can cause local and systemic infections in the patient. The aim of this study was to investigate the effect of antimicrobial materials such as titanium dioxide, chlorhexidine acetate salt, silicon dioxide and amoxicillin in combination with pure PMMA resin in temporary veneers made with 3D printer on the number of cultivated Enterococcus faecalis bacteria colonies. Methods and Materials: In this experimental laboratory study, 50 resin samples (10 samples in 5 study groups) containing one gram of each of the antimicrobial substances along with 100 ml of resin, with dimensions of 1 x 10 x 5 mm by 3D printers were made using DETAX GmbH resin . Each resin sample was placed inside a microplate well. Half Farland suspension of Enterococcus faecalis bacteria was added to each well. After vortexing the samples, the attached bacteria were isolated from the resin and cultured. The data were analyzed using the statistical program SPSS version 26 and Kruskal-Wallis statistical test and Bonferroni's post-test. (P<0.05 values were considered significant.) Results: In this study, the number of Enterococcus faecalis colonies from the highest to the lowest were related to control, titanium dioxide, silicon dioxide, amoxicillin and chlorhexidine acetate salt groups. While the number of bacterial colonies did not differ significantly between the three groups of titanium dioxide, silicon dioxide and control (all cases P>0.05), as well as between the two groups of chlorhexidine acetate and amoxicillin (P>0.05), the number of colonies in Chlorhexidine acetate and amoxicillin groups were significantly lower than titanium dioxide, silicon dioxide and control groups (all cases P<0.01). Conclusion: It is recommended to add the antibacterial substances of chlorhexidine acetate salt and amoxicillin to PMMA resins to prevent the growth of Enterococcus faecalis colonies.