Antimicrobial Potential Evaluation of Silver Nanoparticles Formulation Against E.faecalis Biofilm

Objectives: This study aimed evaluate the antimicrobial potential of silver nanoparticles formulation to use as medication in endodontic therapy against mature E.faecalis biofilm (NCTC 775).
Methods: 20 dentin samples of 3 x 3 x 2 mm which were encubate per 30 days immersed in bacterial suspension of E. faecalis. After the formation and maturation of the biofilm specimens were divided into 5 groups (n=5) in accordance with their treatment: Ag - Silver nanopartcles formulation; HCa - calcium hydroxide pasture; Clx - chlorhexidine 2% (positive control); CV - Maltose + gelatin (control of the foemulation vehicle); ST - Without treatment (negative control). The specimens were immersed in ependorfs containing the respective treatments and encubate for 7 days each. After, the sonication of specimens, so that the remaining biofilm solubilize in solution, followed by the realisation of serial dilution of each group. Once the dilutions, each extracted ependorf had two drops plated on Petri plates containing solid BHI and encubate for 48 h for subsequent counts of the number of colony-forming units in stereoscopic magnifying glass. Parallel this, the initial ependorf dilution had dentin specimens after sonication, removed the ependorf contents was frozen in liquid nitrogen and freeze for later weighing the rest biofilm mass. Thus, in possession of the units colony forming number and the biofilm weight from each group were compared to the amount of bacteria present in each group after treatment with the respective formulations. These values were analyzed and compared with each other by means of ANOVA and Tukey Kramer assay (α≥0,005).
Results: The results showed that the group Ag was statistically similar to positive control and statistically different from groups CV and ST which were statistically similar among themselves.
Conclusions: In this way, it was concluded that silver nanoparticles formulation are potential antiseptic agents to be used in root canals.