TÍNH KHÁNG KHUẨN ENTEROCOCCUS FAECALIS CỦA DUNG DỊCH NANO BẠC VÀ KHẢ NĂNG ỨNG DỤNG NANO BẠC TRONG ĐIỀU TRỊ NỘI NHA

Abstract

Objectives: (1) To determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgNPs (5 - 7 nm) solution against E. faecalis bacteria. (2) Evaluate antibacterial effectiveness of AgNPs solution at the minimum bactericidal concentration against E.faecalis cultured in tooth roots for 21 days. Method: This in vitro study consisted of two parts. Part 1: Determining the minimum inhibitory concentration of AgNPs solution using the microdilution method on a microplate plate. Then determine the minimum bactericidal concentration of AgNPs according to the bacteria culture method on agar plates and the Real-time PCR testing method. Part 2: Irrigation the roots which were cultured of E.faecalis bacteria for 21 days with following solutions: group A (10 teeth) irrigated with 0.9% NaCl; group B (10 teeth) irrigated with AgNPs solution at minimum bactericidal concentration. Take a bacterial sample after irrigation with an absorbent paper cone in the root canal and perform a Real-time PCR test. Compare the average Ct index of the groups to evaluate the antibacterial effectiveness of AgNPs solution at the minimum bactericidal concentration against E.faecalis bacteria cultured in tooth roots for 21 days. Results: The minimum inhibitory concentration of AgNPs solution determined by microplate dilution technique was 62.5 ppm. The minimum bactericidal concentration of AgNPs solution determined by the bacteria culture method on agar plates and Real-time PCR testing method is 62.5 ppm. Results of irrigation in the tooth root after culturing E. faecalis bacteria for 21 days showed that 62.5 ppm AgNPs solution was as effective against E.faecalis bacteria as 0.9 % NaCl solution (p > 0.05). Conclusion: The minimum inhibitory concentration and minimum bactericidal concentration of AgNPs (5 -7 nm) solution is 62.5 ppm. The antibacterial effect against E. faecalis was cultured in tooth roots for 21 days of 62.5 ppm AgNPs solution equivalent to 0.9 % NaCl solution.